Grissom, newly appointed head of the crime lab, investigates the supposed suicide of a jackpot-winner. Meanwhile, Warrick has to deal with the fact that the shooting of rookie CSI Holly Gribbs was due to his failure to supervise her.

Department protocol is violated when Catherine investigates her ex-husband's rape accusation.

A Jane Doe is brutally attacked and raped before being left to die on the side of the road. With two bullets lodged in her brain, she is in a deep coma. Catherine and Warrick work on an open case of a man killed by his neighbor. The statements from the accused and the deceased's wife contradict each other.

Grissom, Sara and Warrick investigate the apparent hit and run of a young man...they soon discover he was deaf. Meanwhile, Nick and Catherine are attempting to solve a mass murder in a coffee shop.

A woman is found dead at a spa while a young man is found burying dead bodies.

The death of a woman named Mona whose body was dumped in a sand pit leads Grissom and Catherine to a fetish club run by Lady Heather. Since Mona was a dominant, Lady Heather was surprised that her employee was tortured and suffocated to death. This leads Grissom to conclude that the victim was a 'switch', someone who could play both the dominant or the submissive role.

A casino was brutally but clumsily robbed by at least four trigger-happy fiends, the men of which wore female wigs. Painstaking identification efforts lead to ex-con serial killer Tammy Felton and accomplices, but one by one is found murdered themselves. The solution comes only after links are found with the bizarre shooting of a desert hamlet's only store's clerk, discovered by state trooper William Spencer, who messed up the crime scene despite long experience.

When a young woman riding a horse finds a body of a woman inside a pipe in a construction site, Grissom and his team investigate the murder. Soon they find another woman's body and coroner Dr. Albert 'Al' Robbins notes that the women are very different despite being sisters. Their further investigation indicate the Donna Marks was a reclusive woman, maybe agoraphobic, while Joan Marks had a different behavior. Meanwhile, Catherine and Nick investigate the murder of the hunter James Jasper in the woods. James was an insurance broker and an experienced hunter, but was not wearing the safety vest. Catherine, Nick and Detective Vega learn that Jasper and his wife Linda had lost their jobs. When they find a one-million dollar life insurance on behalf of Linda, his wife becomes their prime suspect.

A world-famous poker champion drops dead in the middle of a game. He appears to have had a heart attack. Outside of the city, Nick and Catherine investigate the death of a young street racer.

Boxer LaRoi Steele didn't survive his third fight against Javier Molina, whom he defeated in both earlier encounters. Grissom works out what happened exactly and why after learning how that Vegas show discipline really works. Nick wanted a solo case but isn't tickled-pink with a jewelry theft, yet does it well enough to counter abuse from ingrate victims. A gang fight involving an arrogant 'modern' gangster turns out to tie in as well.

A taxi driver accidentally runs over a teenage boy. He is later brutally beaten by a gang who thinks he is running away. Grissom and Sara works on the case and finds that the boy was dead prior to being hit from a stab wound.

A body falls out of the sky, literally. The cause of death is suffocation but the body bears no signs of strangulation.

Matt Phelps sends his two kids to bed, and out of the blue, there is a drive-by shooting and his daughter Aimee is shot and killed in her bed. Grissom, Warrick and Capt. Brass investigate the case and Grissom learns that Matt Phelps is Warrick's mentor and friend. Warrick's investigation is conducted based on his emotions instead of on the evidences with serious consequences for Matt and a suspect. Meanwhile, Nick and Sam Vega investigate the mysterious death of a boss of a four-men Internet service company in the air-conditioned servers' room. They find many secrets in the team but no suspect and no murder weapon. Until Nick observes the duct of the air-conditioning.

When Joanne Crooks is assaulted without rape at home, Catherine, Grissom, Nick, Warrick and Capt. Brass assume the investigation. They find fingerprints on the windows and they learn that the criminal is escalating in his crimes. They fear that he soon will rape his victim since this was his first break in. Meanwhile, Sara learns that the paraplegic prosecutor Melissa Winters will be submitted to a surgery of high risk. Three years ago, Winters was shot on the neck in a home invasion where her husband as killed, but the murderer has not been found. Now the bullet has moved and she needs the surgery. Sara decides to reopen the cold case using the bullet withdrawn in the surgery to try to find the criminal.

A team of robbers heist the First Monument Bank and Detective Cyrus Lockwood is shot and murdered. The team investigate the case and find that the thieves wanted a specific safety deposit box in the vault. Meanwhile the driver of the getaway van is found dead in the vehicle, Larry Whiting. He was a former valet of the Rampart Casino, owned by Sam Braun. When they find the name of the owner of the stolen box, Benny Murdock, an Catherine recognizes the name.

Sheriff Rory Atwater is leaving the Orpheus hotel and witness a car bombing, where the driver, the valet and the bellhop die. Grissom and Catherine arrive to investigate the crime scene and gunshots start. Grissom finds that the bullets are in the trunk in bag. Nick and Capt. Brass help the investigation. Soon they learn that the driver is Air Marshall Adam Watson, and the car was rented in an agency. Nick puts together the pieces of the bomb, which was a pipe bomb connected to the car clock. Soon they conclude that the victim might have been the previous user of the rented car since the timer was not accurate. Meanwhile, Sara, Warrick and Det. Louis Vartann investigate the death of Amelia Reuben, who is the wife of the successful singer Myles Reuben. They conclude that Myles, his manager Sam Hopkins and a hotel waiter were the last persons to see Amelia alive, and the autopsy and Greg's investigation concluded that she was poisoned.

Teenager Brian Haddick is found on a construction site, skull fatally smashed, with an employee's hammer. Grissom's team checks on the construction crew as well as Brian's school crowd, stumbling on abused love and dirty practices. Another victim was killed by a bullet which literally fell from the sky.

There is a heist in a supermarket with five casualties, including police officer Clay. The entire CSI team investigates the case. Officer Fromansky, Grissom's longtime foe and who killed the robbers and a civilian, claims that there was a third robber on the scene. However, the evidences do not corroborate with his testimony. The CSI proceed the investigation and conclude also that it was an inside job. Will they find the truth?

While giving his testimony in a retrial, Grissom sees fingerprints on a matchbox that he does not recall. The victim Max Larson was found dead I his hardware store hit by a wrench. He requests a recess to the DA and reopens the investigation of the case. He follows the protocol and assigns Catherine, Warrick and Nick to investigate the case again and why they have missed the fingerprint in their investigation. Ecklie asks Sofia to investigate Grissom's cases and begins a witch hunt in the laboratory. Meanwhile, Sara, Greg and Det. Louis Vartann investigate the case of a John Doe, who died after shooting his own leg. When they succeed to find the register of the gun, they find clue of another case.

When the young mother Lori Kyman is reported missing by her husband, Grissom and Sofia meets with Capt. Brass on the highway where her car was found with flat tire. Sara and Capt. Brass go to Lori's house to interview her husband Mark, and they find her best friend Amy Maynard. Lori's stepmother Diane Hoyt arrives and confirms Mark's alibi. Soon Greg finds that the valve of the flat tire in Lori's car was unscrewed leaking the air, and he finds prints. Meanwhile, Catherine, Warrick and Nick investigate the deaths of the hunter Rod Hollis with claws around his neck and a Kodiak bear in the woods. However, the animal is not native from the area. In the autopsy, Dr. Robbins finds that bear was shot twice, by Hollis' rifle and by a Magnum .357 that was used in a robbery and belongs to Aaron Colite. A microchip in the bear shows that he belonged to Clark County Zoo and was bought by a broker.

CSI team goes back to investigate crime scenes as a team, re-united together after the traumatic experience in season five finale. Nick's kidnap case audio tape arrives at the laboratory.

Catherine investigates the murder of a young mother who claimed God got her pregnant, while Grissom witnesses a very shady trial.

After a massive shootout between the LVPD and a Latin American mob gang, the CSI team have to find and process hundreds of bullets to determine exactly what happened.

The CSIs continue to process the evidence collected from the high-speed chase. They must also find the bullet which killed a police officer to determine who shot him.

The CSI's investigate the death of a very hairy man. At a quick glance, the body can be easily mistaken for a werewolf. The man died from a gun shot wound. He, along with his sister, has a rare genetic disorder which causes excessive hair growth.

The murder of a man in a garage leads the CSI team to the daughter of the man who abducted and buried Nick alive earlier.

A man walks into a shabby apartment and shoots the occupant. On his way home, a teenager's car crashes into his car. Ally Sullivan insists on calling the police but the man refuses. As he leaves, he sees her texting her phone. Thinking that she's calling the police, he kills her. The CSIs have a hard time finding this killer as he knows how to cover his tracks really well. He is truly a professional.

The death of three unidentified teenagers lead the CSIs inside the world of rap music.

While Jim Brass is in surgery the team has two cases to tackle. The first involves a man, found decapitated on train tracks, with a 19-inch waist. Further investigation reveals that he wore a wasp corset, as was fashionable with gentlemen during the Civil War. The other crime scene is in a hotel room where a man is found in his boxers, dead, on the bed. Scattered around the room are evidence of a wild night of alcohol, drugs, and sex. Ellie, Brass's estranged daughter, comes to visit her father from LA.

Keppler proposes that Catherine create a phony crime scene to help catch a murderer, and to keep it secret from the other investigators. However, Nick quickly figures out that something is fishy.

With Grissom out of his office and all of the detectives out in the field, Hodges and the lab other techs try to discover new clues in the miniature killer case.

Hodges puts the lab techs through a series of "murder games"--a set of bizarre, hypothetical murder scenarios which all take place in the lab.

A mobster that Warrick had a run-in with is found dead, and Warrick is found at the scene with the murder weapon. However, he insists that he has no recollection of the crime.

CSIs past and present come together at the news of Warrick's death. But will Warrick's real killer successfully frame another police officer for his murder?

The CSIs dig to find the truth about how a recent shootout at a gun store might connect to a young woman who may have committed suicide.

A comic who was one-half of a legendary Vegas duo from the 1970s is found dead on the eve of their reunion show, while the body of a fugitive who bombed an abortion clinic is dumped in Las Vegas with over 100 bullet holes in him.