Sam Ryan assists the police in the investigation of a multi-vehicle collision that results in the death of 11 people. She is joined by two new colleagues: Dr. Leo Dalton, an experienced pathologist from Sheffield and Dr. Harry Cunningham. As they try to determine the causes of the accident, they find a severed arm that does not belong to any of the victims. They also have to deal with DCI Carol Deacon whose role in the investigation is not quite clear to them. Sam and Leo have somewhat different approaches to their job, particularly in how they deal with the police. Harry performs his first autopsy on a child.

The mystery of the severed arm is partly solved when the police discover a body floating in the river with a missing arm. The pathologists continue their investigation with little help from the police and DCI Deacon in particular. When she reveals to Tom that two of the men in the accident were undercover policemen, he realizes that Sam was correct and that he is being manipulated. The police refuse to tell them what is going on and Sam's interference has serious consequences. Harry continues to try and find a balance between detachment and compassion as one of the survivors of the crash seeks his assistance.

The police investigate an apparent break-in that results in the death of Derek Irons, his wife and youngest daughter. Two older children survived the attack but one is in serious condition and in a coma. Irons was a ruthless businessman who targeted his rivals' customers resulting in regular confrontations. Irons was stabbed but his wife and daughter were shot. Sam is reunited with an old friend from Northern Ireland, Det. Supt. Tony Ashton who is the senior investigative officer on the case. Harry assists the police with the death of an old woman who is believed to have fallen down a staircase. His post-mortem reveals evidence that is not consistent with a fall.

The police continue their investigation into the deaths of several members of the Irons family but based on the forensic evidence, they now believe he may have been killed elsewhere and then transported to his home. When one of Irons' two surviving children is killed, they look to his circle of friends and family for a possible motive. Thanks to Harry's information, the police investigate further into the death of an elderly woman who supposedly fell down the stairs in her home. Supt. Tony Ashton clearly wants to renew his friendship with Sam but she isn't so sure. Leo's home life is in turmoil and it's been affecting his work.

When a decomposed body is found hidden in the wall of an old factory building, Sam Ryan concludes he was murdered. He is eventually identified by his ex-girlfriend Selina Thomson as Marcus Saul, who had simply disappeared one day some seven years earlier. There has also been a break-in on campus and drugs have been stolen. The Dean asks Leo Dalton to speak to some of the students on the issue, but he's not quite sure what he can do.

With the death of a student from a drug overdose, the university must face the wrath of the girl's father, a major benefactor. The autopsy reveals that not only had she taken drugs but also that she had sexual relations with three different men in the previous 48 hours. Although the police have a suspect in the murder of Marcus Saul, new information suggests that the identity of the killer may lie in a completely different direction.

The police may have a serial killer on their hands when they locate a second body in a site where the first victim was found several months before. The body was trussed up in the same way and had an identical burn mark on his back. There is no apparent link between the first victim, student Michael Haughty, and the second Jason Villers, a probationer at the police college. While the police find evidence that may solve the Otty case, they have nothing on the Villers murder. In a separate case, Harry is approached by the wife of an old university friend who asks him to perform a post-mortem on her husband who died in a fall. Harry finds that his old friend was injecting himself regularly. Leo's family is visiting for a few days but he's constantly being called into work.

When a second police probationer dies at the police college, Sam concludes that they may be dealing with a copycat murder rather than a serial killer. The investigating officer thinks that a fellow probationer may have been responsible for the original murder but the college's commandant, whose son is a student there and soon to be a police constable, would like the reputation of the college protected and the whole thing swept under the carpet. Harry learns that his late friend's wife was prescribing the drugs he was taking and is not quite sure what to do with the information. Leo's relationship with his wife and daughter is stretched thin when he spends most of his time at work and they are left on their own.

In a suspected terrorist attack on a London hotel a government minister is killed. As Sam and the team investigate the case, old friends and government officials soon muddy the water.

Refer to part 1, as this is the continuing story of that.

Sam comes under intense scrutiny during an official inquiry into the deaths of two brothers while they were in prison. Her findings are soon challenged by her colleague, Leo Dalton, who is brought in to perform a second autopsy. Meanwhile, a series of murders that are taking place cast suspicion on a recently released ex-convict. He served years in prison after being convicted of killing his wife; the evidence against him was given by Sam during one of her very first cases. During his time in prison, however, he continued to deny his guilt. Sam begins to believe that someone is stalking her, while the police have trouble locating the ex-convict.

Sam and Leo, colleague Pathologists, are on opposing sides of a high-profile court case.

A John Doe is found months after his death; an attractive female agent for a championship athlete is believed to have jumped to her death from a rooftop. Forensic pathologists must sort out time and methods of death.

Sam Ryan steals a toothbrush to get the DNA of the father of the unborn child of a suspected suicide. Tangled relationships between an athlete and his family are amplified when his body is found hanging in her apartment. Police arrest the athlete's brother-in-law after an anonymous tip. Harry's attempts at determining time of death by the growth of maggots give a wrong answer.

Questions about a celebrated pathologist's accuracy in past cases leads to several exhumations; Sam Ryan is assigned to reexamine the remains. One particularly brutal murder conviction depends on the time of death being precise. Two crucial witnesses are found: one on her deathbed, anxious to get something off her chest, and the other dead behind a remodeled wall.

Sam is determined to find out how Dr. Sachs is able to pinpoint time of death so precisely, even if it means several convictions are overturned. A mother changes her plea to guilty, but Leo is still not satisfied that they have the truth. A loving daughter draws a picture for her prisoner dad that brings a confession. Dr. Sachs is found to have violated professional ethics, but what will serve the cause of justice best?

The team is called out to Northern Ireland to investigate the bodies of two men killed by paramilitaries twenty years ago. For Sam, it is a case that is soon to turn personal.

The Lyell Center team solve more than just the original case that took them to Northern Ireland. Professor Ryan makes peace with her past and takes control of her future.

Tensions are running high in the 'leaderless' team as Leo and Harry clash over an investigation into an outbreak of breathing difficulties among children on the South Coast.

The team is approached by a support group of survivors from a recent train crash. What caused the tragedy, and what is the identity of the unidentified Body 21? When the mysterious body is named, Harry and Leo get closer to finding out what caused the train crash - with tragic consequences for one of the heroes of the disaster.

Harry is called out to a death at a racecourse. A jockey was killed when his horse pulled up and fell, crushing him to death.

The police and Harry find that a group of doctors are in a syndicate that owns race horses. One is a kidney Specialist and another is a Plastic Surgeon with a gambling problem. A young woman is going to pay for a kidney transplant privately as the National Health Service wait list is long. She and her husband wish to have a baby after that. There is a helicopter accident and it all becomes a complicated story to figure out for the team of Pathologists who have a temporary visitor called Nicki who is borrowing the lab to obtain a narrative about an Iron Age family whose bones she has to examine.

The team investigates the derailment of a train caused by someone leaving Maj. Mark Wiltshire's Land Rover on the tracks. The army is suspected but Wiltshire was in the officers mess at the time. The team have yet to identify the 21st victim, or determine if that person was on the train or in the car. Working with a survivor's group, they try to re-create where everyone was seated just prior to the crash occurring. When one of the survivors commits suicide, the crash claims its 22nd victim.

The investigation continues and one of the survivors remembers a vital piece of information. It becomes evident that the identification of body 21 may also lead to the cause of the crash. In the end, the solution rests on discovering a an unknown romantic affair and marital betrayal.

The team is shocked when Leo Dalton's wife and daughter are killed when a fancy sports car careens out of control and smashes into a café. The police are puzzled by the cause of the crash but believe the driver may have been involved in a identity theft ring when they find several several passports and ID cards in the vehicle. Meanwhile, Nikki must perform urgent autopsies on two bodies found floating in the river. When she finds fingerprint evidence linking one of the bodies to the car accident, it becomes apparent that the two cases are linked and the police may have been less than forthcoming about their investigation.

Unsatisfied with the progress of the case, Leo Dalton takes matters into his own hands trying to get in contact with an identity theft ring. The information he gathers assists the police and they work together. The death of one of the gang members, and a vital clue, lead police to identify the their leader, but in the end, the solution brings little solace to Leo.

The team is called to a drive-by shooting outside a London nightclub. They arrive to a scene of carnage with several people dead, or dying.

With the murder of the club manager, the pathologists also determine that the club owner shot his own girlfriend, likely by accident. They also identify an unlikely suspect in the shooting of the club manager. Harry and Nikki confront Leo over his abusive and unprofessional behavior.

Harry investigates the death of a woman who drowned in a backyard pool. She was apparently struck on the side of the head and her husband claims that her expensive necklace is missing. Leo and Nikki investigate the death of Lucie Philips, a kidnap victim who was taken a week previously. The girl's father tried to pay the ransom but the money was never collected leading the police to believe that the kidnappers may have had other motives. They also investigate the murder of a pizza deliveryman that has similarities with the Philips crime scene. A third murder leads the police to suspect that they may be seeing the work of a serial killer. Nikki's grandmother dies bringing her into contact with her estranged father.

Leo and Nikki find yet another victim who was apparently bound and buried alive. However, they continue to have difficulty finding a common link among all of the victims. The investigation focuses on the editor of a philosophical journal who had an intellectual disagreement with one of the victims but the case is more complex than first imagined. Harry discovers that his drowning victim was pregnant which may have indirectly contributed to her death. Nikki's father is released from prison and promptly disappears.

The team investigates two deaths, the first a suicide where someone jumped to their death and the second where a paranoid schizophrenic dressed as a vicar goes on a rampage stabbing innocent bystanders. Their suspicions are aroused when they learn that both men were receiving treatment at the same clinic, January House. Leo assists the police in their investigation of a building society employee who is forcibly taken from his house and subsequently found dead in his own car. Harry is asked to perform an autopsy and provide a second opinion in the death of a young woman. The death was ruled a suicide, but the mother refuses to accept the verdict.

The Director of January House tries to take his own life on the clinic grounds and the pathologists suspect they may have a case of adulterated prescription medication. Harry's repeat autopsy reveals that the young woman was also under medicated, but she had no contact with the clinic. The police suspect the wife in the case of the building society employee and Leo sets out to disprove her time line.

When a boat carrying illegal passengers is found crashed in the Thames, the team investigate.

The team follows the trail of the people traffickers, and has to find any remaining survivors before a highly contagious disease breaks.

Harry investigates a case of hit and run where the victim was a 16 year old boy from the nearby housing estate. Working with Sgt. Susan Fenn, they attempt learn if this was an accident or intentional. Harry takes quite a liking to Susan and is shocked by a sudden turn of event. Leo examines a death resulting from a house fire where the lady of the house died. He is puzzled at why she was unable to leave and the police immediately suspect the husband, who was in a nearby park with the children, of murder. Nikki looks into the case of a young woman who collapses at her hen night. She had recently had minor surgery and was taking pain killers, but there is surprising information to be found about her background.

The pathologists busy week continues with a variety of cases. Nikki examines a death in a telemarketing office. Several workers were vying for promotion and the police suspect foul play. Harry deals with the case of a professional footballer who committed suicide. He realizes there is a link to another case he is working on. Leo deals with the case of a drunk who died on a bus. There is little information about the man and the case becomes more of a puzzle when the autopsy reveals that he wasn't drunk at all.

Harry is shocked when his former university girlfriend, Penny Harris, is brought in dead. She drove her car into a tree and the police initially suspect suicide but the autopsy reveals that the medication in her system was ground rather than in pill form, so they conclude she was likely murdered. Her husband tells the police that he thought his wife was having an affair and her parents react strangely to the news. Leo assists the police in the death of Jimmy Triangle, a conceptual artist whose latest work dealt with the death of conceptual art - and includes his own body, as he is shot through the head. The question is whether the shot was self-inflicted or not.

Nikki and Harry continue to investigate the death of Penny Harris. Harry is shocked to learn that she had apparently at some point in her life had a child but her husband denies any knowledge of such. Another death in the Harris family allows them to narrow the suspects and identify the killer. Leo continues to look for clues and the police think they have solved the case through fingerprint evidence, but Leo is able to prove that the suspect has been framed. The victims penchant for videotaping his activities provides a vital clue.

Alison Garland is a 14 year old schoolgirl found dead on the school grounds just after lunch. She appears to have slit her wrists and committed suicide, but there is also evidence that she had sexual relations just earlier that day. As Leo Dalton looks into the case he learns that Alison was also a school bully and was a very unhappy young woman. Harry assists the police in the stabbing death of a car dealer. The evidence suggests that he was stabbed in his garage and his body then dumped. The case takes a radical twist when they find that the knife found by Alison's body was also used to kill the car dealer. Nikki assists the police in the death of an elderly woman who appears to have been maltreated.

A third murder is discovered on school grounds and Leo realises the killings are connected to a sinister teenage pact. Meanwhile, Nikki proves her elderly victim died of hypothermia - but there is still a guilty party to be caught.

Harry and Nikki deal with the case of a young woman who is found dead in an animal shelter. Her dead body has obviously been posed and the autopsy reveals she may have been tortured before death. Information from police intelligence suggests that they may be dealing with a group of radical animal rights activists. It all becomes quite personal for Harry when Nikki is taken prisoner. It's also a difficult time for Leo who has been asked to appear before a medical council hearing and testify on the propriety of a close friend's medical research. Harry has been offered a prestigious chair at an American university, but has had difficulty discussing the issue with his colleagues, especially Nikki.

Harry and the police desperately search for Nikki as they continue to find more bodies. The animal rights activists' target is a well known pharmaceutical firm that is undertaking research on behalf of the government. Leo finally decides on a course of action in testifying at the medical council hearing.

The pathologists investigate when a military helicopter crashes into a refugee detention center. Harry and Nikki actually witnessed the crash and were first on the scene but the case is complex since the center was Ministry of Defense property leased to the Home Office. The team is shocked at the conditions they find in the center and Harry, who has a close friend in the RAF, is shaken when a government Minister attributes the accident to pilot error.

Harry is convinced that the RAF is trying to cover up the real reasons for the crash. This is re-enforced when the dead pilot's father tells him that no one liked or trusted the particular type of helicopter that crashed. When given a chance to perform the post-mortem on the pilot, they find a possible physical cause however. In examining one of the dead refugees, Nikki concludes that he had undergone plastic surgery. She attempts a facial reconstruction to see if they can identify him.

Leo Dalton investigates the death of a young boy whose body is found in the river. He was badly abused and his hands and feet were severed. The child is found to have been HIV positive and the pathologists determine that he may have been the victim of a ritual killing., perhaps as part of an exorcism that went too far. When the skeletal remains of another child are found, Leo believes the police have focused their investigation on the wrong man. Nikki Alexander investigates the apparent suicide of Father Anthony Reid who appears to have jumped from his apartment window on the grounds of a well-known Catholic school. He had colon cancer but those who knew him question that he would take his own life. Harry Cunningham looks into the case of Austin Chambers who is found floating in his swimming pool with an obvious ligature mark on his throat.

When a second person, Vincent Fricks, is found dead with ligature marks around his neck, Nikki and Harry not only find a connection between the two dead men but also with the school where Father Reid committed suicide. They also find another common link between the three. Leo Dalton continues his investigation into a local church that combines Christian with African beliefs and customs. He manages to find physical evidence linking one of the dead boys to the church.

Harry Cunningham investigates when a car accident reveals two bodies inside one coffin. The coffin contained the body of 80-year-old Ethel Mortimer, who was supposed to be there and also that of James Featherton, a high tech sales rep who also had a heavy cocaine habit. Leo Dalton and Nikki Alexander have to deal with the death of a young child who died post-operatively. The pediatric surgeon in the case, Alice Huston, is well known in her field but may be prone to undertaking aggressive surgeries. The pathologists find a connection between the two cases when Featherton's girlfriend is found to be a nurse on Huston's surgical team.

With Claire Kowalski missing and Nikki Alexander unconscious from a blow to the head, Harry and Leo investigate exactly what is going on at the hospital. Harry discovers that a member of Huston's surgical team is not who they claim to be and has actually stolen the identity of someone who died six years before. Blackmail is at the center of it all and it turns out Alice Huston is hiding a secret. However, the killer is identified only by looking to old friendships and the calling in of an old debt.

Nikki Alexander finds herself working on a case from her past. Four years previously, she had been instrumental in getting 17 year-old Anna Holland acquitted of a murder charge. She had been accused of egging on her boyfriend in the murder of a young mother they chose randomly. Now, while under police protection, her body has been found in a burnt car. The autopsy reveals that she had been stabbed but had died from carbon monoxide poisoning and so was burnt alive. Nikki also receives a surprise visit from her estranged father who wants her to perform a second autopsy on a friend who recently died.

Nikki Alexander begins to have serious doubts about her conclusions four years previously when her testimony helped acquit 17-year-old Anna Holland of murder. Anna's mother had withheld information from the police and as Nikki reconstructs the scene of the crime, she realizes that the blood spatter evidence no longer holds up. The police focus on the dead woman's husband but the pathologists find that a series of unsolved murders may have a bearing on the case. Nikki is also annoyed with her father, who has conned Harry Cunningham into completing a second autopsy on his late wife.

Harry Cunningham is asked to review a case in a insurance dispute. The insurance company is refusing to pay out on an policy when the autopsy results show that the woman was intoxicated and likely was responsible for the fall that killed her. Her family insists that that is impossible as she was an abstainer. Nikki Alexander investigates when human remains are found buried in an field. The locals believe the body to be that of Clara Young, who had disappeared 18 months before. The remains are found on the site of a travelers or gypsy caravan site and the police are convinced that George Wood, one of the camp residents is responsible, but Nikki's evidence proves otherwise.

George Wood is released by the police but he is soon found dead in his caravan. Although made to look like a suicide, it is clearly a murder. The case gets even more complicated for Nikki and the authorities when she determines that there are the remains of two victims in the field, not just one. The evidence in the George Wood murder points to someone with connections to the police. Harry Cunningham believes that the dead woman in his insurance case was likely suffering from dementia and looks to prove the cause

Following a court appearance for drunk driving, Leo is required to perform unpaid work as a punishment, assisting AJ, a community worker on a run-down,largely black-occupied housing estate in South London. AJ is hoping to divert boys away from crime by encouraging them to do sports, and, though initially dismissive of Leo as a white intruder, comes to respect him after he has saved the life of Errol, a former gang member now anxious to keep his little brother Levi out of trouble. Errol has been stabbed in the leg by members of a gang from a rival estate and Leo stops him from bleeding to death. Earlier in the week a young girl called Shana Block was stabbed to death at a funfair and her murder recorded on a mobile phone. As Shana lived on the estate police sergeant Wallace involves Leo as a go-between with the suspicious residents. Also on the scene are Harry and Nikki, the latter dating Ryan, a young Scottish paramedic she met when called to the scene of Shana's death. Before any arrests can be made, Richard Ojana, a member of a rival gang, is shot in broad daylight and nobody is willing to come forward as a witness. Believing he knows who the killers are, Errol goes off into the night, but the next day his corpse, tarred and feathered, is dumped on A.J.'s recreation ground.

The examination of the latest body from the housing estate proves it to be that of Errol Harris who was asphyxiated while being tarred and feathered. The policeman in charge of the case, DS Nick Wallace, is exasperated at the lack of physical evidence the pathologists are able to provide him as without concrete proof of who is involved in the killings, he knows they will never get a conviction. Leo Dalton thinks that the key to getting information is Errol's younger brother Levi who is actively being recruited to join the gang. Tragedy ensues however after the police question the boy. Finally at their wit's end, Leo comes up with a piece of evidence that has been available from the very beginning of the case.

The team is called in to identify the corpse of a woman whose face was surgically removed after death. Janet Mander, a Home Office anthropologist, cannot link it to similar murders but, after Nikki has reconstructed the face, Holly, a medical student on work experience with Harry,recognizes the woman as Fran Price, an investigative journalist. Pargeter, her agent, is evasive and Supt. Barker, the investigating police officer, does not help as he is obsessed with the idea that Leonid Polyak, a Russian criminal Fran helped to put behind bars, has ordered a hit on her from his prison cell. Whilst Leo gets closer to Janet, Harry is concerned when he sees Barker entering Holly's flat and later she is found murdered in her bed.

Everyone is affected by Holly Farr's murder. The pathologists find that she was tortured and beaten but died from having her throat slit. The police believe that her death is related to that of Fran Price and the recent leaks of forensic evidence to the press may have led the killer to her. Supt. Barker decides to put armed policeman to guard each of the three pathologists but Harry Cunningham, who saw Barker go into Holly's house, is suspicious of his true motives. When a prominent Russian, Oleg Kolik, seeks asylum in the UK saying he is the true target of the Russian assassins, Harry thinks that Fran Price may have been targeting him in her new book. When Leonid Polyak is murdered while being transferred between prisons, he decides it's time to put his job on the line in the pursuit of justice.

The team is called in after Mr. Stickley of the Police complaints Board feels that something is not right about an armed police raid on a house where several people were killed, including one of the officers and a mystery woman. A young Muslim called Melik has been badly wounded and lies in hospital. Mr. Stickley believes the policeman was killed by Rhys Allen, a colleague who was having an affair with the deceased's wife. Melik's sister Isra confides in Nikki that all the 'suspects' were unarmed and not terrorists and fears of a cover-up by the authorities are not helped by the aggressive attitude of Inspector Transfield, particularly when Nikki is attacked and evidence stolen from her laptop.

Harry Dalton and DI Helen Okoroafor manage to identify the dead woman from the scene of the raid - who turns out to be a DS who was working undercover and who the police refused to identify when the pathologists submitted her DNA sample to them. While DI Tranfield continues to search for the terrorist cell that he is sure is about to strike, Nikki Alexander continues to try and piece the evidence together from the scene of the raid but clearly there are pieces missing. A re-creation of the shooting shows her what happened and also identifies the only person in the right position to have shot the police officer.

Harry Cunningham investigates the death of a young Orthodox Jew. He accedes to the family's request that he not use invasive procedures in his examination and finds that the young man was savagely kicked and beaten to death. DI McKenzie has a suspect in custody but from what medical and forensic evidence Harry is able to find, with Nikki Alexander's assistance, it's obvious that the family is lying about the young man's whereabouts the night he was killed. Leo Dalton meanwhile investigates the death of a young student who died from a drug overdose. Leo is uncomfortable with what he finds, particularly that she had sex with one of the men at a party when her boyfriend was in the next room. He thinks she may have been given GHB.

With a second member of the Orthodox Jewish community dead, Harry performs a complete examination. This time, Harry does not hesitate to use all examination methods at his disposal and finds forensic evidence that clearly links a third member of the Hassidic community to both deaths. After DI MacKenzie makes the arrest however, Harry realizes he may have inadvertently contaminated the DNA evidence leading to a false result. Nikki retests all of the evidence and together they figure just who the attacker was. Leo Dalton meanwhile tries to prove that the dead student had been given GHB. He concludes that someone also tried to administer CPR.

The half-naked corpse of a twelve-year-old boy is found in his school grounds and Liam, the child in whose company he was last seen, has disappeared. Nikki is particularly involved because the school's head teacher,Noel Hopkins, is the teacher who, years earlier, encouraged her interest in science.

A severely mutilated corpse is found on a railway line, belonging to a known paedophile in his twenties, Francis Neil. Noel Hopkins is arrested, following revelations years earlier of an affair with a young pupil Nikki believes to be Francis but he is released due to insufficient evidence, though he is sacked from his job and his house torched, his saviour being Danny, father of the dead boy Michael. It is ultimately revealed that in fact Liam did not exist - he was the 20-something Francis, obsessed with Michael, and both were victims of the paedophile ring. Ultimately Nikki helps Noel to overcome prejudice and regain his job.

Stephen Harrington, a friend of Leo, is concerned that his daughter Rachel, an aid worker, has gone missing in Zambia. Leo and his colleagues fly to Africa where Rachel's corpse is discovered. It seems that she was investigating the deaths of local villagers and may have been silenced. In the absence of the local coroner, the team get involved but find that uncooperative police officers are not exclusive to Britain.

With another aid worker now dead, the pathologists are trying to piece together just what Rachel was up to. Dr. Andrews tells them that Rachel had been trying to trace the source of an infectious disease that she believed had been affecting many of the local villagers. She had originally believed that the disease was water-borne but all tests had proved negative and was therefore looking at other possible sources. Yet another death however strikes the local ex-pat community. With tensions rising, Nikki finds herself in jail and and Harry getting the cold shoulder from the local coroner.

Insurance investigator William Byfield is found gassed in his car after he has sparred with Nikki over a claim for terminally-ill suicide Sally Craven. He was also perturbed about the suspicious death of one Stephen Connelly, which leads to Leo being accused of falsifying the post mortem by William's successor, Clare Ambler. In fact Connelly's details never reached Leo and his widow, bereavement counsellor Rebecca, is not only uncooperative with Clare but is Harry's current girl-friend and overly friendly with coroner's officer David Levin. When it appears that William Byfield was murdered Harry suspects Rebecca of being involved.

Now Leo is under investigation by the police over the discrepancies in Stephen Connelly's file. He think he's found the solution when he notices similarities between the Coroner's file on Connelly and another case he had worked on. Harry is convinced that his new lover Rebecca, Connelly's widow, has nothing to do with the apparent forgeries Leo has found. He believes that the fraud is taking place at the Coroner's office and focuses on David Levin, who had access to the information. After Leo is assaulted outside his home, he is hospitalized and in a coma. On the edge of death, Nikki and Harry learn they may have a major decision to make. When the police find Leo's blood in Rebecca Connelly's home and Levin's body in the boot of her car, they are convinced they have the killer. No one however realizes the true deception that is taking place.

Left wing writer Tom Flannery rings for the emergency services when he finds his investment banker wife Bridget dead at the foot of their stairs, lying in an unnaturally large pool of blood. Both Harry and Detective Superintendant Jenkins find the death suspicious as some blood seems to have been cleaned from the wall, making a 'void', but then Jenkins dislikes Flannery's anti-police strand in his writings and she knows Bridget was insured. Nikki believes the death was an accident until Bridget's sister Muriel tells her that the first Mrs. Flannery also died after falling downstairs.

At the coroner's inquest into Bridget's death Nikki and Harry give conflicting evidence though it turns out that a young policewoman made the 'void' when she slipped on the blood and touched the wall to steady herself. Disturbed mental patient Diamanda Yannis,who had previously attacked Tom's daughter Anna, a nurse, was seen at the Flannery house, covered in blood but she dies after a fight with police. Harry has the first Mrs. Flannery exhumed, proving that someone killed her. Tom admits to Nikki it was him,during a drunken argument over his wish to marry Bridget. He also claims that he killed Bridget but Nikki believes he is shielding somebody else.Is he?

Ruth Gardiner falls to her death from a squat in a high-rise block and Leo - unlike D.I. Neill - realises that she was murdered though Neill seems reluctant to launch a public appeal. Ruth's father tells Leo she left home two years earlier, he assumes to join a cult, but had phoned recently to say she was retuning to him.Reading of the death car salesman Phil tells his girlfriend Danielle that he is an undercover cop working with Ruth - who was staking out a resident in the flats. Danielle meets with Leo, telling him Neill is corrupt and anxious to shut down Phil's operation,which is to expose sex trafficking. Phil - real name Peter Carmody - takes Alex Webb, an apparent suspect,to a caravan where he will be safe. Harry, meanwhile, discovers that a recently deceased family friend had had an affair with his mother.

Carmody goes on the run and Danielle is killed. The same man's DNA is found in her flat as on Ruth's corpse. Leo's partner Janet persuades him that Neill is not dishonest and Neill discovers that Carmody is a car salesman working with Webb. A failed police college entrant some years ago, he has persuaded his wife and mother - as well as Ruth,Danielle and Webb - he is an undercover cop though when Janet interviews his mother she says that he was a fantasist since childhood. Clearly he is a loose cannon, rubbing out those who discover his secret and must be found. Harry discovers that his father was a bully, driving his mother to having an affair.

The team attend at the apparent suicide of student Jason Renfrew at the local university. The Dean tells Leo Jason complained to her about racist bullying and he is found to have swallowed a chip containing photos of the alleged bullies, as well as having a handgun in his locker. Soon afterwards a gunman goes on the rampage, killing several people including the policeman investigating Jason's death. Nikki and Harry are trapped in a classroom with some students, one of whom, the mortally wounded Matt Frisk, was one of Jason's tormentors. Commander Somerville leads the police team who release them though it is Harry who finds the severely injured gunman. However, he fails to spot the bomb planted on campus.

Harry suspects that Scott Weston, the injured gunman, was shot by another person and it becomes obvious that two guns were used in the massacre. Scott's mother tells Dean Mears that Scott and Jason were good friends, Scott looking out for the more fragile Jason. Meanwhile Nikki is held prisoner in the deserted mortuary by unbalanced Neil Corrigan, who appears to have planned the massacre with Jason - who chickened out and killed himself - and then framed Scott. Ultimately video evidence reveals what actually happened, as well as locating the bomb.

The pathologists travel to South Africa, Nikki Alexander's childhood country. Nikki has been there for a short while and with the help of a now imprisoned official from the former regime, they've uncovered the grave of five activists who were eliminated. The problem is that they find a sixth body in the grave. Nikki is also developing feelings for the man who has hired her. Meanwhile, Harry is working with a local pathologist investigating the murder of a young girl. Leo is a bit late in arriving as he was trying to help a young girl who had requested asylum in the UK. He arrives in South Africa only to learn that the young woman has been deported.

Nikki thinks that the sixth body is that of the long missing son of her former nanny, whom she goes to visit. Harry accompanies Sara and her policeman husband as they recover the dead body of Nyasha, killed as an 'example' whilst Daya is returned to the sinister orphanage. Mandisa, the official who took Kudzai there, tells Leo it is a safe haven but it is really a brothel,trading in illegal immigrant girls with no families and the two girls found in the harbour were killed there by brutal patrons and then dumped. Leo leads the police to the brothel and the girls are saved. Nikki, however, faces a far more bitter truth as she realizes Anton has not been honest with her.

Pathologists investigate three deaths in one night in the same ward and suspect hospital staff of their murder.

In her efforts to help Naomi, Nikki believes that Silverlake was self-medicating with an untried depression cure though his widow denies it and a representative of the pill company, posing as a health inspector, tries to have Nikki taken off the case. After she is arrested for shop-lifting and feels perpetually tired, Nikki is referred to a psychiatrist who diagnoses depression. Naomi is highly supportive throughout but, at the hospital, the police make a frightening discovery which questions Naomi's motivation. Even after the real murderer is punished another death occurs, leading to closure for Nikki.

Nikki's archaeologist friend Patrick is excited when a woman's body,apparently a thousand years old,is unearthed on a Yorkshire moor. However dental records show she is a more recent murder victim and Leo,who once worked in the area,believes she is Jodie Fisher,who went missing in 1985. Three other girls were murdered and the killer,Karl Bentley,caught and jailed. Leo,unsuccessful in his efforts with Janet to make a baby and applying to adopt,reencounters Jodie's mother,old flame Carol,before visiting Bentley,who creepily says that his actions were 'out of love'. Then another woman is killed.

Janet travels to Yorkshire with Leo where she identifies the murder of the fresh victim,Kelly Summers,as being a copycat of the Bentley killings,suggesting that Bentley had an accomplice still at large. This is confirmed when Sonia Hardwick,the investigating officer,finds a letter to Bentley from a boyfriend in the original file. A television crew visits the Fosters' farm house,where Carol's husband Bill snaps,attacking a journalist. He is arrested and interviewed by Sonia regarding his relationship with Karl Bentley. Between them Sonia and Leo deduce that Bentley had a male lover responsible for the unsolved murders and that that man is Bill Fisher. They are only partly right. Harry,meanwhile,has to baby-sit the teenage son of an irresponsible old college friend.

At Hillsdon Army base,a training camp for soldiers fighting in Afghanistan,young soldier Mark Blakefield is still recovering from the death in action of his friend Danny Ferris and argues with Lieutenant Lockfield,who was having an affair with Danny's girl-friend 'Cats' Felton,a fact which Lockfield's wife Claire has also discovered. Cats' body is pulled from the river some time after she was talking to the lieutenant and Nikki suspects foul play. Then Lockfield is shot,an apparent suicide,but Harry,accompanying Inspector Suzy Harte to the base,finds from the post mortem result that the man was murdered.

Nikki links Cats to the Lockfords via her phone and,at her flat,sees photos of her with her boy-friend Danny,whose father identifies her corpse. The police catch a man skulking at her flat,Dennis Croft,a former soldier cashiered for drug peddling who says there was a cover-up over Danny's death. At the request of Danny's parents a further post mortem is carried out,ultimately proving that he was killed by 'friendly fire'.Consequently it transpires that Lockford was not seeing Cats for sex but seeing her right financially. CCTV evidence shows that Cats' death was due to a bizarre accident but who killed the young lieutenant and why?

Harry is in Budapest with Anna Sandor, a lawyer committed to women's rights who wants him to perform a second autopsy on Sofi, a pregnant Romanian prostitute drowned in the Danube. Anna disbelieves the official version that Sofi killed herself but the body is quickly cremated and Anna is murdered. Harry is pursued by the gangsters who killed her, hiding out with street dweller Janos, who tells him not to trust the police. Leo answers Harry's distress call and flies out but Anna's doctor father believes Harry murdered her and detective Orban tells Leo Anna was pregnant by Harry. Harry breaks into Anna's office, finding links to a brothel run by the same tattooed men who pursued him. He and Janos flee but the men shoot them. Leo suspects police duplicity in the gang's ability to locate Harry so quickly.

Nikki flies to Budapest and is called to a secret meeting with Leo to avoid Orban. Harry appears, having faked his death to pursue his enquiries. From another prostitute Marina he learns that the gang use the girls to produce babies for influential people who, for various reasons, cannot have children of their own. If the girls are HIV positive like Sofi, they are killed, a fact that Anna had uncovered. Harry approaches Anna's father who says he knew what was happening but wanted to shield Anna from it, before dropping another bombshell. With the British ambassador and other dignitaries involved in the plot, the pathologists have to trust Orban if they are to bring an end to the racket.

Nikki and Harry are called to the Dutch Embassy in the wake of a gunman killing three people,including police constable Barlow and the brother of ambassador Van Buren,though the latter officially died three years earlier. Van Buren's son Jacob went missing fifteen years earlier and now his grandson Jack is missing, Jack's mother Klara and young policeman Whitehead being among the wounded. Curiously the CCTV cameras were switched off at the time of the shooting but,recovering in hospital,Klara claims the murderer was Jacob. The news coverage has a strange effect on telephonist Mary Olivant,who is found hanged,though Leo finds the death suspicious. He is also wary when another pathologist,Sabiston,whom he once trained,is called in to carry out the post mortems at the ambassador's request.

Mary Olivant turns out to have been the Van Buren's nanny at the time of Jacob's disappearance and a body unearthed near to where her corpse was found is identified as that of the little boy. Diederick Van Buren had been paying her thousands for years but she had recently seen Klara and told her the true fate of her brother. The so-called bodyguard was actually Diederick,allegedly working for MI6,and the pathologist who pronounced him dead three years earlier was Sabiston,working with Superintendant Mansfield in a cover-up on behalf of the embassy. Harry finds Jack,who has gone into hiding and who saw all that happened on the night of the shooting,for which reason he is protecting the killer.

Following the suicide of colleague Lizzie Fraser, who he believes was scapegoated by police for a wrong decision, Leo comes to work in an angry, bitter mood. DI Connie James brings Leo, Harry and Nikki in following the brutal slaying of ex-SAS soldier Mick Francis, his daughter Jessie, and her young son Luke at their farm shop during a robbery. Harry establishes a good rapport with the pregnant Connie but then Superintendent Byrne links the murders to that of Lizzie's sister Mary twelve years earlier and to several other unsolved murders in the intervening years. Byrne believes the killer is a drug-addicted woman known as the Wraith, working with a male accomplice. However unknown to him a hooded white boy who was at the shop would seem to fit the bill.

An eye witness account and identification of a car links a youth called Lee Ness to the farm shop murders but he claims not to know the Wraith. Tom Byrne,recently widowed,and Nikki,who has just lost her father,develop a rapport whilst interviewing the parents of another supposed victim of the Wraith,who have their own views on the murderer's identity. A discrepancy in the findings of the Wraith's DNA at different crime scenes leads Harry to take samples from a rival laboratory. The result reveals an elaborately plotted revenge scenario to punish the police for the deaths of Mary and Lizzie.

When Nikki sees barefoot teen-ager Shannon Kelly run over by a car whilst fleeing somebody she sits with her until the ambulance arrives and later visits her in hospital,where it is clear she is frightened of a man. DS Masood tells Nikki Shannon has been sexually abused and suspects Abdul,her estranged stepfather. Shannon turns up at Nikki's and reluctantly agrees to go back to hospital. Meanwhile a gang of young Asian men are picking up and grooming white school-girls for the sex trade. They already have Shannon's friend Amy and go after two more,Hannah and Lauren. The pathologists investigate two seemingly unrelated cases - the remains of a young girl found in discarded airport luggage and a heavily tattooed man,John Dear,who died of toxic poisoning. Then a third corpse is found - that of Amy.

Through a DNA link the pathologists find that John Dear was a client of unwilling child prostitutes Shannon and the deceased Amy whilst the suitcase victim is also identified. Nikki visits Shannon in hospital and learns about the gang of abductors but the young girl is too scared to name names. Through CCTV DS Masood gets the car registration number of a visitor to Shannon and arrives at a taxi firm where Salman,a somewhat reluctant and kind-hearted gang member, works. Salman helps Hannah and Lauren escape but is killed when his taxi crashes. The three girls are returned home but will not speak about their ordeal and,with Abdul swearing revenge, Nikki must help DS Masood resolve matters. The case closed Harry announces that he is leaving to take up a professorship in New York.

Leo gives evidence at a custody hearing in the wake of a child's death,his opinion over-ruling that of Dr Helen Karamides,which annoys her former pupil Nikki,who sees Helen as the victim of the male establishment and cannot believe the accusation that Helen is retaining tissue samples from past cases. Nikki is also approached by Andy Farmer. His mother Annie was the appropriate adult at the interview with serial killer Arnold Mears,who now directs Annie to the sites of his victims' remains where she collects their bones. Andy wants Nikki to help identify them. Nikki also discovers that Helen had a professional involvement with Mears.

Leo feels guilty when Helen kills herself,leaving an explanation on Camcorder that she took the tissues to further scientific research. Aware that Mears killed more women than he was imprisoned for, Leo tells the police about the arrangement with Annie,scaring Andy, who believes that Mears will have his mother murdered for the breach of trust. It is also revealed that Annie believes her daughter was one of Mears' victims,hence her involvement with him. When Annie disappears Nikki visits Mears,who agrees to tell her about all his other victims. He appears to have won his mind game with her but his possessiveness over his copy of 'Paradise Lost' and Nikki's chance remark about an elderly lady she met who knew Mears yield results.

Harry's work colleague Justine Thompson is murdered in her house with her daughter Gemma whilst her stepson Charlie, also attacked, lies in a coma. Baby daughter Ellie, however, is unharmed. Husband Stuart is prime suspect but he has an alibi and his grief seems genuine. The post mortem shows that Gemma was pregnant and the team learns that Justine once needed a restraining order against Stuart's brother Kevin, who was obsessed with her. Mrs Barron, the lady from next door who found the bodies, finds evidence on her son Joel's computer that Gemma and Charlie were lovers as Joel rides off to see Kevin.

After Kevin dies in a motorcycle crash Harry is surprised to see Joel keeping a vigil by Charlie's hospital bed. Whilst denying murder Joel professes that he loved Gemma was shocked that she was sleeping with Charlie. Stuart's initial alibi breaks down when CCTV footage shows Kevin, not him, at the hotel in question but he admits to an affair with Mrs Barron. The murderer is eventually exposed after a shocking betrayal is revealed, leading to an horrific reaction.

Prison inspector Rachel Kruger is murdered,along with young Nick Owen,a man she was visiting,whose computer is stolen.Inspector Bridges tells Leo she reckons Rachel's husband Peter killed his wife and her suspected lover but Peter claims that Rachel was in danger because she was investigating sinister events at Redhill prison,particularly the mysterious death of convict James Wade,and Leo believes him. The team joins the police investigation of Redhill,where governor Cairns is less than helpful and Rachel's original source,Dr Ross,too scared to speak out. But, unbeknown to the pathologists, Bridges knows far more than she is letting on.

When prison officer Ellis Roberts and convict Benjamin Johnson are killed after a supposed cell fight Leo is suspicious of corrupt officer Kessler,whose evidence about the fight does not ring true and is found to have fathered a child with Andrea Bridges before he left the police under a cloud. Nikki persuades Bridges to confess that she covered for Kessler in the past but,despite Kessler visiting Leo to threaten him,there is doubt that he murdered James Wade and the prison inspectors Kruger and Owen. The eventual discovery of the truth spells bitterness for both Leo,ending his relationship with Janet,and Harry.

Leo is called in by his old college friend,psychiatrist Sean Delaney,now a cancer-stricken alcoholic. Sean was treating inspirational,deeply religious teenager Eve Gilston,who felt neglected by her family ,and the verdict of whose death,alone in bed,apparently of arrhythmic death syndrome Sean does not believe. Accompanied by down-to-earth sergeant Brooks Leo interviews Eve's parents,lapsed Catholics Beth and Tony,wondering if the family is prone to the rare heart condition Long QT Syndrome,though John,their blind younger son refuses to be tested. Sean tells Leo that,at their last session, Eve believed that she was possessed by evil and soon afterwards Leo and sergeant Brooks find evidence that a priest performed an exorcism on her.

Shocked by the news of the exorcism Sean joins Leo in visiting Father Jacobs though he tells them that he did not perform the exorcism and Nikki tracks down the nun,Sister Landsley,who did so,only to find she has killed herself. Leo believes the trauma of the exorcism triggered Eve's death but then he learns from Beth how Eve thought that she was possessed after passing on the measles which blinded him to John when they were younger. With the knowledge that his grandmother killed herself John believes that possession runs in the family and now he is host to the demons, leading to a further exorcism.

Nikki flies to Budapest and is called to a secret meeting with Leo to avoid Orban. Harry appears, having faked his death to pursue his enquiries. From another prostitute Marina he learns that the gang use the girls to produce babies for influential people who, for various reasons, cannot have children of their own. If the girls are HIV positive like Sofi, they are killed, a fact that Anna had uncovered. Harry approaches Anna's father who says he knew what was happening but wanted to shield Anna from it, before dropping another bombshell. With the British ambassador and other dignitaries involved in the plot, the pathologists have to trust Orban if they are to bring an end to the racket.

With a second member of the Orthodox Jewish community dead, Harry performs a complete examination. This time, Harry does not hesitate to use all examination methods at his disposal and finds forensic evidence that clearly links a third member of the Hassidic community to both deaths. After DI MacKenzie makes the arrest however, Harry realizes he may have inadvertently contaminated the DNA evidence leading to a false result. Nikki retests all of the evidence and together they figure just who the attacker was. Leo Dalton meanwhile tries to prove that the dead student had been given GHB. He concludes that someone also tried to administer CPR.

Harry is in Budapest with Anna Sandor, a lawyer committed to women's rights who wants him to perform a second autopsy on Sofi, a pregnant Romanian prostitute drowned in the Danube. Anna disbelieves the official version that Sofi killed herself but the body is quickly cremated and Anna is murdered. Harry is pursued by the gangsters who killed her, hiding out with street dweller Janos, who tells him not to trust the police. Leo answers Harry's distress call and flies out but Anna's doctor father believes Harry murdered her and detective Orban tells Leo Anna was pregnant by Harry. Harry breaks into Anna's office, finding links to a brothel run by the same tattooed men who pursued him. He and Janos flee but the men shoot them. Leo suspects police duplicity in the gang's ability to locate Harry so quickly.

Nikki and Harry continue to investigate the death of Penny Harris. Harry is shocked to learn that she had apparently at some point in her life had a child but her husband denies any knowledge of such. Another death in the Harris family allows them to narrow the suspects and identify the killer. Leo continues to look for clues and the police think they have solved the case through fingerprint evidence, but Leo is able to prove that the suspect has been framed. The victims penchant for videotaping his activities provides a vital clue.

Harry Cunningham investigates the death of a young Orthodox Jew. He accedes to the family's request that he not use invasive procedures in his examination and finds that the young man was savagely kicked and beaten to death. DI McKenzie has a suspect in custody but from what medical and forensic evidence Harry is able to find, with Nikki Alexander's assistance, it's obvious that the family is lying about the young man's whereabouts the night he was killed. Leo Dalton meanwhile investigates the death of a young student who died from a drug overdose. Leo is uncomfortable with what he finds, particularly that she had sex with one of the men at a party when her boyfriend was in the next room. He thinks she may have been given GHB.

When Nikki sees barefoot teen-ager Shannon Kelly run over by a car whilst fleeing somebody she sits with her until the ambulance arrives and later visits her in hospital,where it is clear she is frightened of a man. DS Masood tells Nikki Shannon has been sexually abused and suspects Abdul,her estranged stepfather. Shannon turns up at Nikki's and reluctantly agrees to go back to hospital. Meanwhile a gang of young Asian men are picking up and grooming white school-girls for the sex trade. They already have Shannon's friend Amy and go after two more,Hannah and Lauren. The pathologists investigate two seemingly unrelated cases - the remains of a young girl found in discarded airport luggage and a heavily tattooed man,John Dear,who died of toxic poisoning. Then a third corpse is found - that of Amy.

The team is called in to identify the corpse of a woman whose face was surgically removed after death. Janet Mander, a Home Office anthropologist, cannot link it to similar murders but, after Nikki has reconstructed the face, Holly, a medical student on work experience with Harry,recognizes the woman as Fran Price, an investigative journalist. Pargeter, her agent, is evasive and Supt. Barker, the investigating police officer, does not help as he is obsessed with the idea that Leonid Polyak, a Russian criminal Fran helped to put behind bars, has ordered a hit on her from his prison cell. Whilst Leo gets closer to Janet, Harry is concerned when he sees Barker entering Holly's flat and later she is found murdered in her bed.

The pathologists busy week continues with a variety of cases. Nikki examines a death in a telemarketing office. Several workers were vying for promotion and the police suspect foul play. Harry deals with the case of a professional footballer who committed suicide. He realizes there is a link to another case he is working on. Leo deals with the case of a drunk who died on a bus. There is little information about the man and the case becomes more of a puzzle when the autopsy reveals that he wasn't drunk at all.

Everyone is affected by Holly Farr's murder. The pathologists find that she was tortured and beaten but died from having her throat slit. The police believe that her death is related to that of Fran Price and the recent leaks of forensic evidence to the press may have led the killer to her. Supt. Barker decides to put armed policeman to guard each of the three pathologists but Harry Cunningham, who saw Barker go into Holly's house, is suspicious of his true motives. When a prominent Russian, Oleg Kolik, seeks asylum in the UK saying he is the true target of the Russian assassins, Harry thinks that Fran Price may have been targeting him in her new book. When Leonid Polyak is murdered while being transferred between prisons, he decides it's time to put his job on the line in the pursuit of justice.

Through a DNA link the pathologists find that John Dear was a client of unwilling child prostitutes Shannon and the deceased Amy whilst the suitcase victim is also identified. Nikki visits Shannon in hospital and learns about the gang of abductors but the young girl is too scared to name names. Through CCTV DS Masood gets the car registration number of a visitor to Shannon and arrives at a taxi firm where Salman,a somewhat reluctant and kind-hearted gang member, works. Salman helps Hannah and Lauren escape but is killed when his taxi crashes. The three girls are returned home but will not speak about their ordeal and,with Abdul swearing revenge, Nikki must help DS Masood resolve matters. The case closed Harry announces that he is leaving to take up a professorship in New York.