The pilot for the popular TV series is set during 24 frantic hours in the lives of a group of doctors, nurses, and staff members of a busy emergency room at a Chicago hospital. They deal with the seemingly endless casualties that stumble into their place of employment. The central characters are the chief resident and family man Dr. Mark Greene, who is considering a job in private practice due to pressure from his demanding law student wife Jennifer; outgoing Dr. Doug Ross, who deals with cases in his own personal way; straight-arrow Dr. Susan Lewis, trying to get by another long 36-hour shift; inexperienced third-year med student John Carter; cocky surgical resident Dr. Peter Benton; and troubled chief nurse Carol Hathaway.

Mark's wife arrives in the ER with the news that she has passed her bar exams but several members of the staff interrupt their intimate celebration. Greene treats an elderly woman whose husband isn't ready to let her go. It's been eight weeks since Hathaway's attempted suicide, but Doug Ross has yet to bring himself to visit the woman he went out with for two years. Susan Lewis saves a newborn who is brought into the ER choking. She also argues with the psychiatric attending who refuses to admit a patient suffering from dementia. Carter finds himself having to care for a group of German tourists who are suffering from food poisoning. He also treats a young flirt with a rash. Benton treats a recent surgery patient and finds his correct diagnosis overturned by the man's physician. Susan Lewis treats a family struck by a drunk driver. The husband and daughter will survive but there is little hope for the woman. The drunk driver is also brought in suffering from only a few scratches.

Carol Hathaway returns to work after her suicide attempt. Doug Ross still feels guilty about what happened. An ER patient found walking the streets takes to singing, constantly. Susan Lewis has a run-in with the cardiologist on duty, Dr. Kayson, when he disagrees with her treatment of a heart attack victim. At a case review session, she gets very little support from her colleagues. She also treats a woman who is dying of leukemia and who has good advice for Hathaway. Greene treats a woman who has obviously been beaten by her husband but can't get to agree to get help.

Drs. Benton and Langworthy are unsuccessful in reviving a teen-aged boy involved in a traffic accident and it's left to Carter to determine the boy's identity and notify the parents. Unfortunately, he tells the wrong parents that their son is dead. Doug Ross tells a young patient that he will not be separated from his schizophrenic mother knowing that she will likely be hospitalized for a long time. Susan Lewis tells Mark that she is dating the psychiatric attending physician Div Cvetic. She also treats a salesman whose cell phone is having an odd effect on hospital equipment. Benton forgets that he was supposed to sit with his mother while his sister and brother-in-law were to go out for their tenth anniversary dinner.

Mark Greene's wife Jen gets a position clerking with a Federal judge. Unfortunately, it's in Milwaukee, 2 hours away and she wants Mark to look for a job there. Greene and Susan Lewis treat Samuel Gasner, a man who has been waiting for a heart transplant and who will not survive the night unless a donor can be found. John Carter is worried that his latest paramour may have left him with a souvenir of their sexual encounter. Doug Ross treats a young girl suffering from severe asthma but whose mother can't afford her medication. Benton treats Ivan the liquor store owner who is shot for the third time in as many weeks.

The realities of the ER may be too much for a child, but circumstances force Greene to bring his daughter Rachel with him on a day when the outdoor temperature tops 100 degrees and the air-conditioning doesn't work. Benton and Langworthy try in vain to save a boy shot in self-defense. Meanwhile, Lewis's broke sister, Chloe, steals Lewis's TV and VCR. After Ross crosses the line with Hathaway and Taglieri, Hathaway slugs Ross.

Doug Ross' hopes of renewing his relationship with Carol Hathaway take a positive turn after the two of them kiss following a particularly stressful trauma, but his hopes are dashed when she decides to move in with boyfriend Tag. John Carter has a particularly good day when Dr. Green successfully walks him through a complex procedure. Haleh takes Dr. Benton to task when he refuses to act as a role model for a young gangbanger she has an interest in. Benton is also competing with Dr. Langworthy for a prestigious fellowship. It's Susan Lewis' birthday and her sister Chloe shows up at the ER drunk.

Susan Lewis' boyfriend Div Cvetic, a psychiatric resident at County General, seems to be under a great deal of stress regularly lashing out at everyone. Doug Ross takes over for Mark Greene who takes a day off to be with his wife. He has a hard time keeping up with all the paperwork. John Carter is increasingly frustrated with Peter Benton who never seems to invite him to participate in surgeries. Benton learns the result of the fellowship he applied for and his mother shows up in the ER with a sprained ankle. Carol Hathaway treats a patient who was raped. A new ER aide, Bob, start work.

Carol Hathaway faces an ethical dilemma when a patient admits that he, and not his friend, was driving the car that ran a red light and killed a pedestrian. She decides to tell Tag about kissing Doug Ross. It's Thanksgiving and the doctors treat an animal rights activist who was attacked by the turkey he was trying to save. Doug Ross is going to the Bahamas with Linda Farrell and he is very much feeling like a kept man. Carter has to treat a transgender woman who has now reached an age where she can no longer pass as a woman. Carter's indifference is the final straw. Susan Lewis continues to worry about Div Cvetic, whose condition seems to be worsening.

The ER staff's slow snow day becomes chaotically hectic when the casualties of a 40 car traffic accident flood in.

It's Christmas-time and the expected range of emotions is to be found among the ER staffers. Susan Lewis treats a middle-aged woman who is overjoyed at finally getting pregnant. Susan is also shocked to hear that her boyfriend Div Cvetic has quit his job and moved out of his apartment. Mark Greene treats a young drowning victim. Doug Ross takes Greene's advice and decides to tell Carol Hathaway that he loves her; unfortunately he chooses to do so at her engagement party. Peter Benton jumps the gun and arranges for transplant teams to harvest an accident victims organs but the man's wife is now refusing to give consent. Susan's sister Chloe announces that she is pregnant.

Susan Lewis has a run-in with Dr. Jack Kayson, the cardiology attending, when he accuses her of not providing him with all necessary information on a patient who subsequently died. He makes it very clear that Susan will bear all responsibility for his death. Her sister Chloe informs her that she and her boyfriend are moving to Texas. John Carter is still frustrated by Peter Benton's apparent lack of interest in teaching him anything but a new go for it attitude leads to an invitation to assist in a surgical procedure. Benton's sister suggests to him that the time has come for them to put their mother in a care home.

Benton is called out of surgery to find his senile mother.

Dr. Kayson becomes Lewis' patient.

Dr. Greene gets offered a new job by Morgenstern.

Kayson, a married man, tries to start a romance with Susan by asking her to dinner. Deb unknowingly eats LSD-laced chocolates. Carol takes an interest in a Russian girl abandoned in the ER.

It's a day of birthdays. Peter Benton's mother is celebrating a birthday and he tries desperately to find someone to cover his shift. He makes a choice however when Dr. Hicks suggests that he's been absent too often and may wish to consider a leave of absence until his mother's situation is resolved. Carter thinks it's Benton birthday and has a surprise for him. Mark Greene's daughter is also having a birthday but he misses that due to an emergency at the hospital. An elderly, solitary man in the final stages of cancer arrives in the ER on his birthday. Carol Hathaway suggests to her fiancé that they adopt little Tatiana, the AIDS patient abandoned in the ER. Ross has to deal with a young child who was kicked out of a window.

Carol Hathaway goes ahead with her plans to adopt Tatiana, but her past history makes her ineligible. Benton continues to trade shifts so he can spend time with his mother but it all catches up with him and he has a run-in with Dr. Hicks. Doug Ross treats an abused child. Green, Benton and Carter take extraordinary measures to save a man they later learned had signed a DNR. A consultant arrives to study procedures in the ER, but all is not quite what it seems. Mark Green's wife Jen has an important announcement. Benton's mother has a serious accident when he falls asleep on the couch.

Dr. Benton has to deal with the aftermath of his mother's fall and crosses the line with the surgical attending when he insists on scrubbing in for her operation. Dr. Greene deals with Jodi O'Brien who is two weeks away from giving birth. With the obstetrics attending unavailable, he decides to try to deliver her baby in the ER, with tragic results.

Dr. Greene is still haunted by the death of Jodi O'Brien and isn't sure he can function as a doctor. At Susan's urging, he takes the night off but unfortunately for him, the new head of the ER Dr. 'Wild Willy' Swift arrives unannounced. Susan impresses Swift with her handling of many cases on a busy night. She also has to deal with the case of a young man who has had the hiccups for two days but may in fact be suffering from something far more serious. Nurse Hathaway and fiancée Tag are still working out the details of their wedding. Peter Benton's mother is still hospitalized and he will not accept that her age and her injuries mean that she will need permanent nursing care. Dr. Ross is now dating Diane Leeds. John Carter and Deb Chen's attempts at oneupmanship is starting to take on ridiculous proportions.

Dr. Greene is still having trouble dealing with cases in the ER and the new Chief of the ER is growing increasingly concerned. Greene also faces a difficult peer review to examine his handling of the Jodi O'Brien case. Dr. Benton takes on the difficult task of telling his mother that she must be placed in a home with full-time care. Susan's very pregnant sister Chloe returns to live with her. Dr. Ross deals with the case of a young girl with a heart condition while Ross and Carter encounter a patient who refuses treatment for tuberculosis. When Benton asks Deb Chen and Carter to submit their procedures book in a few days, Deb feels she has to get a few more procedures under her belt if she's to best her fellow student. Unfortunately, her eagerness leads to near tragedy for a patient.

Greene finds his marriage falling apart and is concerned at how little time he's spending with his daughter. He also treats an eight week old child with a heart murmur who requires surgery. Susan tries to get her pregnant sister Chloe to take her pregnancy seriously, but her head isn't quite into it. Benton tries desperately to find a surgeon who will operate on a 16 year-old with a severe brain aneurysm that could burst at any time. He's also concerned at his mother's care and is growing ever more attracted to Jeanie Boulet. Doug Ross' commitment to Diane Leeds gets more serious when he agrees to be an assistant coach for her son's little league baseball team.

Doug Ross and Nurse Hathaway treat a girls' basketball team from a local catholic school for meningitis. Their teachers also need to be tested but one of them confides in Hathaway that she may have a particular problem. Green and the Chief of Staff have a disagreement in the middle of a procedure. With the wedding only two weeks away, Tag and Carol Hathaway have to deal with all of the final preparations, not the least of which is writing their own marriage vows. Susan deals with a suicide victim who is using emotional blackmail to keep his girlfriend from leaving him. Susan reaches the breaking point with her sister Chloe and tells her she has to move out.

On a fateful Mother's Day, several staffers in the ER face possible life-changing events. Susan Lewis' sister Chloe gives birth to a beautiful - and healthy - baby girl. Things start to go wrong however when their mother Cookie - who had agreed to take in Chloe and the baby - suddenly decides she's done enough and Susan will have to take care of it. Carter turns down an offer for an ER sub-internship in the hopes that he'll get an offer in surgery. Dr. Hicks has news for him however. Benton's mother takes a turn for the worse. Carol Hathaway is overwhelmed with the final preparations as her wedding day approaches.

It's Carter's last day in the ER and finally fed up with Dr. Benton's apparent indifference, rejoices when he learns that he gets to write an appraisal on him. He subsequently regrets his negative input when he gets offered the surgical sub-internship he'd hoped for and learns that Benton gave him a glowing appraisal. He also spends a good part of the day with young leukemia victim who is fed up with life. Benton and Jeanie Boulet's relationship reaches a crossroads. Mark Greene is offered an attending position at the hospital but also learns that he is being sued for malpractice over his handling of the Jodi O'Brien case. The big day for Carol Hathaway and Tag is here but doubts creep in and one of them gets left standing at the altar.

While victims of a gang shootout are being brought in, Carter is late and a new group of third year medical students arrives.

It's Weaver's first day and she doesn't exactly make a lot of friends. Carol rides along with the paramedics.

Carter gets his first official patient while Doug treats a four-year-old Asian boy who has AIDS.

The feud between Susan and Weaver gets to the point where Mark has to step in.

Doug treats dying Chia-Chia. Mark however feels he's not doing the right thing for Chia-Chia.

Doug and Harper had sex. Mark finds out about this. So does Carter.

Doug saves a kid who's stuck in a flooded culvert and becomes a local hero when a TV helicopter films part of the rescue operation.

Doug gets the opportunity to stay at the ER thanks to the publicity surrounding his rescue of a drowning boy the week before.

Jennifer and Rachel have been involved in a car accident and Mark rushes to Milwaukee where they're in the hospital.

Mark has to deal with the fact he can't see Rachel during the holidays and takes care of a Holocaust survivor whose grandchild is missing.

Shep and Raul enter a house with about a dozen abandoned and ill-fed children and bring them to the ER.

Benton has to attend a banquet at Vucelich's home and asks Jeanie to go with him. Mark hesitates to tell Rachel about the divorce.

It's his day off, but Mark shows up for work anyway. After a patient dies and Morgenstern wants to speak to him, Mark soon regrets coming in after all.

Rumour has it there's something going on between Mark and Susan while Benton questions Vucelich's study and confronts him.

Benton tries to save someone who, according to the other surgeons, can't be saved while the ER gets crammed with pregnant women.

Shep and Raul go in a burning house without the proper equipment to save three children.

Carter is very nervous because he's about to get his residency match. Mark changes his look.

Mark has to work for the fourth night in a row while a lot of the staff are absent and the number of patients is towering.

Benton dismisses a patient he hasn't seen who should have been admitted. Carter competes with Dale, a new surgical resident-in-training who once slept with Harper.

In order to avoid having to deal with her personal problems regarding little Susie, Susan wholly absorbs herself in her work.

Susan has therapy to get over losing little Susie and Jeanie's ex-husband is brought in.

Mark Greene strikes a deal with Kerry Weaver - he will support her application for an ER attending position if she in turn will support Susan Lewis for Chief Resident. When Susan doesn't get the job, Mark is told to go ask her why. Carter is finally going to graduate and wants Benton to attend the party his family is throwing for him. Unfortunately, Carter decides to sit with a young patient awaiting a liver transplant and misses his own graduation ceremony. With the news she has received about her former husband Al's health, Jeanie Boulet decides to have herself tested. Doug Ross' girlfriend Karen forges his prescription for percodan. Hathaway's boyfriend, Shep, is refusing to undergo his anger management treatment. Mark's ex-wife Jen tells him that she is going to re-marry. Loretta Sweet asks Greene if he would become guardian to her kids.

It's the first day of Carter's internship. He has a 36 hour shift and overnight he has to cover the ER, the ICU as well as the surgical patients.

While the whole staff is worried the ER might close, Jeanie has her own problems in dealing with being HIV-positive.

Donald Anspaugh has a new method to increase the staff's efficiency, new intern Maggie Doyle joins the ER and Susan asks Mark to come along to Hawaii.

Doug's one-night-stand has a seizure and he brings her to the ER.

While Mark is anxious about Susan's return from her holiday, Doug and Carol ride along with the health mobile.

While on their helicopter flight rotation, Mark and Susan find an injured family of four who they bring to the ER.

Encouraged by Carol, Mark finally asks Susan out. Benton tries to save a boy, despite the fact Doug thinks he's brain dead.

It's Susan's last day. Carol stands up for her nurses when one of them is being rotated to another department.

Carol worries about her physics exam while Mark is heart-broken about Susan's departure and focuses solely on his job.

Mark and Kerry have to create a policy regarding HIV-positive employees, which leads to gossip amongst the nurses.

Carol has to fire two of the nurses. Meanwhile, Gant feels Benton is too hard on him.

Carter feels guilty about Gant's death. Benton doesn't want to talk about it.

Benton can't keep his mind on the job, Mark and Chuny break up and Carol does what she needs to do regarding the fatal error she has made.

Doug treats a dying 17-year old cystic fibrosis patient who doesn't want to be resuscitated. Carter gets to operate on Benton.

Nurse Carol Hathaway is held hostage during a convenience store robbery, then befriends one of the gunmen.

Carol will hear whether her suspension is permanent or not. Mark and Doyle do what they can to get a patient with Down syndrome on a heart transplant list.

Race relations become an issue in the ER when Mark Greene treats two injured teenagers, one black and the other white, and assumes the black kid was a drug dealer. It turns the white kid was the drug dealer and the black kid is a high school basketball star and an innocent bystander. When the black student's older brother confronts him, he begins to question his own impartiality. Carol Hathaway helps a young woman who was drugged with Rohipnol and raped. Benton gets an interesting offer from Dr. Hicks. He also learns that Carla Reece has been admitted to the hospital. Dr. Carter treats a woman with a serious condition but he seems to be the only one who sees it. Mark Greene's daughter ends up spending the day in the ER when her mom has to rush to Florida to deal with a family emergency.

Benton tries to find out if everything's OK with Carla's baby. Carter tries to get a man operated, despite the fact Anspaugh thinks he will die no matter what.

Benton takes a day off to help Carla. Carter finds out Edson falsified a chart.

Jeanie asks Greg to help Al get into a special AIDS-program at the hospital. Olbes brings in her grandfather, who had a stroke.

It's Carol's birthday, Mark is returning to work after being assaulted and Carla goes into premature labor.

Anspaugh is furious when Carter tells him he wants to quit surgery. Charlie is brought in with an overdose. Mark keeps struggling with his beating.

While a film crew is filming in the ER, it's Elizabeth Corday's first day.

Carter is excited about getting his own med student, and Mark and Carol interview candidates for the desk clerk position.

Cynthia Hooper starts as the new desk clerk. Benton and Carla disagree over whether or not their son should be circumcised. Al gets in an accident at work.

His ex-wife Jennifer tells Mark he can't see Rachel until he's got his act together. Reece gets to go home. Al has lost his job.

Carol would like to have a women's and children's health care clinic within the ER. Benton has trouble combining work and fatherhood.

Al wants to move to Atlanta where he got a job offer. Jeanie however isn't keen on moving. Carol talks to Carter's grandmother about the clinic.

Ross and Greene travel to a near-deserted stretch of California to investigate circumstances surrounding a death in Doug's family.

Benton has a very extraordinary and interesting case when he comes across a boy with reversed internal organs.

Jeanie believes she's been fired because she has HIV and fights her dismissal.

Mark treats an old lady who has been brutally raped. Carter's grandmother visits Carol's clinic. After he's touched by Benton, a blind man can see again!

Dr. Anspaugh's 13-year-old son is brought in and Anspaugh asks Mark to look after him. Another old lady who has been raped is brought in.

Kerry starts to doubt the methods of Synergix. Carter tries to help his cousin beat his drug addiction. Jeanie becomes Scott Anspaugh's part-time caregiver.

Another elderly rape victim is brought in. So is the rapist.

Mark rushes out to San Diego when his mother has a serious fall and is hospitalized. When he gets there he finds her suffering from mild dementia and questions the care she is receiving. To his surprise Cynthia Hooper follows him unannounced and uninvited, leading his parents to form a conclusion about their relationship. Mark also learns a lot about his parents' relationship and while he continues to struggle with his difficult relationship with his father, he also learns of some of the sacrifices the man made for his family.

Because of benzene that's been spread, the ER has to close. Weaver gets felled and Carter has to take the lead.

Mark finds out Cynthia has moved. Carter's cousin Chase is brought in because of a heroin overdose. Doug and Kerry clash after she found a flaw in his study.

Dr. David Morgenstern returns after a six-month absence recovering from his heart attack. His new outlook on life however has Kerry Weaver questioning his abilities. Elizabeth Corday decides to start a study on the use of artificial blood in the ER, but the only problem is that she fails to discuss it first with Rocket Romano. Doug Ross decides to apply for an ER attending position. Scott Anspaugh suffers a major relapse. Anna Del Amico is confronted by an irate husband who wants his ill wife to terminate her pregnancy. At the free clinic, Carol Hathaway has to deal with the case of an underage high school student who is sleeping with her 40-year-old teacher. Peter Benton hits a pedestrian with a car but Carter helps him out with an important piece of information.

When a compatible bone marrow donor cannot be located, Scott Anspaugh agrees to undergo a new round of chemotherapy, even though there appears to be little point. Doug Ross suggests to Jeanie Boulet that Scott may have agreed to the therapy because of her. Mark Greene has taken on the task of organizing the annual ER banquet only to find that Jerry, on whom he had been relying for much of the preparation, hasn't quite delivered. John Carter confronts his grandmother when he learns that she has cut off funding for Carol Hathaway's free clinic. In the OR, Peter Benton has a major confrontation with Dr. Morgenstern, pushing him aside and taking over an operation. Greene and Weaver criticize Doug Ross over his handling of a sick child and her mother.

Following the incident in the OR, Dr. Morgenstern and Dr. Benton present the case to their colleagues. As a result, Peter Benton finds himself suspended for insubordination pending a full inquiry. Jeanie attends Scott Anspaugh's funeral and has some information to share with the boy's father. Anna Del Amico finds herself ethically unable to perform an abortion and is taken to task by Dr. Weaver. John Carter gets the hospital to take legal guardianship of a patient he feels has been subjected to elder abuse, but subsequently doubts that he made the right decision.

Benton and Elizabeth Corday spend the night together. Corday is shocked when Robert Romano suggests that they go out on a date. John Carter and his grandmother clash over the future of Chase Carter; she wants him cared for at home while John feels he should remain institutionalized where he can continue to receive therapy. Carol Hathaway finally gets around to inviting her mother to a Sunday brunch with her and Doug but is a bit surprised when she shows up with her boyfriend. In the ER, Hathaway comforts a man who is going to die from chemical burns.

Assisted by Carol Hathaway, Doug Ross decides to detoxify a drug-addicted infant in the ER without telling anyone. Jeanie Boulet is feeling rundown and fears that her health may be deteriorating. John Carter is less than pleased when Anna Del Amico's former boyfriend shows up in the ER conducting a study on the need for a pediatric attending physician. Del Amico also has to treat a televangelist who is using her health issues to raise money. Elizabeth Corday is worried that Rocket Romano may be aware of her affair with Peter Benton and that it will affect her fellowship.

At the hospital daycare, one of the child-care workers suggests to Peter Benton that he may want to have baby Reece's hearing checked. Doug Ross dodges a bullet by admitting upfront his error in detoxifying a baby without permission. Having been acting Chief for over 6 months, Kerry Weaver puts her name forward to replace David Morgenstern as Chief of Emergency Medicine only to be told she will have to compete for the job. The doctors treat a couple of Elvis impersonators who sky dive into Lake Michigan. When drugs go missing from the ER, John Carter suspects Anna Del Amico's ex-boyfriend.

Third-year med student Lucy Knight reports to the ER for the first day of her rotation. Greene takes a paternal interest in her, helping her get acquainted, but she gets off to a bad start with the irritable Carter. The rest of the day finds her informing a wife of her husband's terminal condition, comforting a pregnant woman, getting locked on the roof and trying to figure out Weaver's "Tour on Tape."

To save rent money, Carter lives in a medical student dormitory as a resident advisor. While visiting Corday at her apartment, Benton meets her father.

Benton performs dangerous surgery on a bomb-carrying man who was shot at a factory. Dr. Ross receives some good news that Dr. Weaver doesn't embrace, but she has no recourse. Rachel encourages Dr. Greene to help a horse that is in pain. Jeanie Boulet returns from her vacation.

Lucy finally admits to Carter that she doesn't know how to start an IV. Weaver interviews for the job as the ER Chief. Benton keeps his son's disease a secret. Jeanie intervenes when she finds out a liver transplant candidate is drinking again, and later asks Doug if she can be assigned to work for his pedes project in the ER. Corday gets stuck as the intern of dismissive and insulting Dr. Dale Edson.

It's Halloween in the ER, and the medical students throw a party; as a result, Carter decides that Lucy isn't mature enough to take responsibilities. A candidate for the ER Chief position arrives from New York and drives home disappointment for Kerry. Mark screws up when he doesn't recognize a homeless schizophrenic woman is pregnant before treating her. Benton treats Corday to a fun Halloween.

The board decides to extend the search for a new ER Chief, leaving Kerry waiting for a decision. Benton visits a doctor who is deaf and he realizes that there is nothing "wrong" with his son. Mark saves the life of a gay prostitute and then tries to get the kid to avoid reckless behavior. Carter loses his Resident Advisor job because of Lucy, then blames her for not going along with his plan to defraud an insurance company, but she inadvertently leads him to shave off a nasty-looking beard he'd been growing. Corday saves two lives and impresses Benton enough that he decides to request she be his intern instead of Dale's. Carol tries to help an elderly Jewish guy find a place to live.

Carter and Weaver become unlikely roommates. Lucy is having problems with Carter, and Greene picks up on their squabbling. Corday works long shifts which leads to her exhaustion and a critical medical error, causing a rift with Dr. Anspaugh and problems for Benton. Greene has unpleasant flashbacks when he's hazed by the well-meaning paramedics. Jeanie worries when she and Doug treat a young boy whose childlike mother clearly depends on his 6-year sister to make all decisions. Kerry rediscovers her joy of practicing medicine and decides not to pursue the open ER Chief job, which goes instead to a Dr. Amanda Lee.

A man arrives at the ER with his gravely-injured daughter then runs out, presenting a critical situation because he's the only match for her blood type. While Carter and Lucy alternately bicker and work well together as they try to track down the father, blood-supply snafus spur Benton to perform an unprecedented operation on the girl.

Corday faces M&M where the board was discussing the mistake that Corday made after she gave the wrong dosage to a patient. She decides to take the offensive and let the board know how wrong it is for her or any other doctor to work 36 hours. The board decides to do nothing about it, and she later decides to amicably end her relationship with Benton. At the hospital arrives Ruth Johnson who was born 100 years ago in that same hospital and shares some experiences with Carter. Carol is horrified by the truth behind a young boy's fatal shooting.

It's Christmas day in the ER. An 18-year-old boy arrives brain-dead, and Carter has to convince his parents to donate his organs, since a 16-year-old girl needs a liver. Benton risks his career by preventing Romano from operating under the influence. Ross and Hathaway have a religious dispute over how to deal with a pregnant 13-year-old. Corday is charmed by a musician who is facing surgery for prostate cancer. Dr. Lee flirts with Mark but turns out to have some major issues and strange story-telling habits.

Dr. Greene tries to help get Amanda Lee the proper credit she deserves on a paper she wrote. However, he starts to become suspicious of her credentials. An old friend of Dr. Greene recommends him for a NASA mission. Benton's son is having difficulties in day care. Doug and Carol help the exhausted mother named Joi of a little boy named Ricky who has a terminal illness. Carter is jealous when Lucy goes on a date with Dale.

Lucy begins her surgical rotation under Benton and Corday. Romano offers to get Corday's fellowship reinstated and asks her to assist him in surgery. Weaver interrogates Corday, asking if Romano ever sexually harassed her. Corday denies it and concludes that Doyle must have filed charges. Ross jeopardizes a liquid pain medicine study by surreptitiously giving some of the drug to Joi's son, Ricky. Greene discovers the secret and informs Weaver. They decide not to tell Anspaugh because, by violating protocol on a federally-funded trial, the hospital would be unable to obtain research money and Medicare payments for years.

Ross helps the mother of a dying boy; Benton attends a parent/child signing class. Corday doesn't give her account in the case against Dr. Romano. Romano blackmails Corday into dropping her support for Doyle's harassment lawsuit against Romano, but Kerry gets Romano to rewrite his insulting and inaccurate review of Doyle's job performance. The ER unites to help an injured woman who needs to find temporary homes for her many dogs as she gets treatment. Mark treats the hospital janitor, Mobalage, whose injuries suggest he has been tortured in the past. Carter discovers something with one of the med students he is mentoring.

Doug faces possible criminal charges after Ricky Abbott dies when Ross shows Joi how to give Ricky a lethal dosage of medication. Doug is delegated to desk duty, Carol's clinic is shut down for acquiring the P.C.A. machine for Ricky, and Greene and Weaver face future disciplinary action for not reporting Doug's earlier mistakes. Meanwhile, Carter and Lucy discover a mutual attraction, Benton studies with a sign language instructor, and Romano begins his first day as acting ER chief.

When a school bus becomes involved in an accident, Mark assists paramedics with treating injured children; Weaver makes a discovery regarding a colleague.

Benton travels to a Mississippi clinic during his vacation time to earn money for his son's therapy, and becomes a local hero when he uses his medical knowledge to help several residents.

Carter deals with tenant drama at an apartment tower during a ride-along that later has deadly consequences, Lucy has to hide a cancer diagnosis from an ill woman at the behest of the patient's family, Carol finds out she is pregnant, Kerry reflects on her own family issues when an injured wrestler comes to the ER, and Greene continues to help Mobalage, who may be deported if he can't tell the INS about the abuse he suffered in Nigeria.

Greene uses a past trauma to help Mobalage save himself from deportation. Carter applies for chief resident and spends the day in charge of the ER, where he misunderstands a case involving the many broken bones of a baby, while Lucy begins her first psych rotation. Weaver may have found her biological mother, but defies a DNR order to find out for sure. Benton and Corday clash over a surgical fellowship.

Carter mentors a talented teen from a very rough neighborhood. Romano is upset about Benton's interest in the fellowship. Lucy continues impressive work in her Psych rotation, treating a law student with homicidal impulses and an angry youngster who is being severely over-medicated. Jeanie continues to grapple with her Hepatitis-C but gets a huge boost from a kindly minister. Hathaway reveals she is pregnant after a kid kicks her in the stomach, risking her baby. Greene and Corday attempt to go to a ball for trauma physicians but end up getting lost repeatedly while having a lot of fun hanging out together.

Romano observes the ER, and rubs the staff the wrong way. Lucy finds out that an elderly patient's bedsore is really much more. Carter breaks up with his girlfriend. The power goes out at County General, and the doctors must keep critical patients alive. Corday investigates the rape of a comatose patient.

The ER has to deal with a stripper and some shady dealings from apparent FBI agents. Lucy reveals to Carter that she's still on Ritalin. Hathaway begins to reveal her pregnancy to those closest to her, including a fax to Doug. Dr. Anspaugh decides that the trauma fellowship will go to Benton, who then faces anger from Romano and Corday. A car accident involving teenagers may have been alcohol-related and leaves one teenager with grievous third-degree burns.

The rest of the staff finds out that Hathaway is pregnant. Benton begins a custody battle for his son when Carla Reese reveals an intention to marry Roger and take the child to Germany. Weaver rescues a toddler that has been drugged. Carter's protégé is mugged and beaten up. Greene and Corday fall in love.

When Anspaugh decides to retire as chief of staff and return to surgery, he appoints Romano as his replacement. Greene expresses reservations about the decision, but Weaver does not support Greene. Romano makes Weaver the new chief of emergency medicine.

After his mother's funeral, Dr. Greene comforts his father (JOHN CULLUM) in San Diego. In Chicago, Romano surprises Corday by appointing her associate chief of surgery. Corday treats Elaine, Carter's lover, for breast cancer.

A recommendation from Weaver allows Jeanie to have temporary approval as a foster parent for baby Carlos. Reggie and Jeanie get married. Lucy and Kovac talk with a young woman whose husband they believe is very dangerous.

Hathaway befriends an out-of-work waitress, Meg. Seven-months pregnant, Meg cannot afford prenatal care. Hathaway invites her to the hospital, performs free tests and helps her interview for a job in the cafeteria.

A prank in a high school science class goes terribly awry, injuring a teacher and several students. Hathaway discovers Meg's drug addiction. Weaver and Greene notice Lawrence gets easily confused.

Benton struggles with the idea of taking a DNA test to determine whether or not Reese is actually his son. As the signs continue to pile up, Kerry and Mark use a fake patient to convince Dr. Lawrence of his Alzheimer's. Carter has trouble persuading a woman from a nursing home fire to sign a DNR for her husband and later is asked to forge charts for a family with no insurance. Carol continues to meddle in Meg's life, having her arrested so that she can be detoxed. Cleo is blamed for an explosion in the suture room but it may actually be Dr. Dave's fault.

Weaver tries to save the life of a rape victim while Corday struggles with feelings of disdain as she is forced to save the rapist. Cleo treats a teenage alcoholic boy whose alcoholic mother refuses to recognize her problem or his.

On Thanksgiving Day Carol goes into labor. She's able to get to the ER only thanks to Luka's help. She delivers the first baby in the ER, but the second causes some trouble. Greene leaves Elizabeth to deal with his father and daughter, as he rushes to assist Carol.

Kovac and Haleh take care of Hathaway's twins so the new mother can finally get some rest. The job transfer for Carla's husband does not get approved allowing Reese to stay in Chicago. Lucy endeavors to get a heart transplant for a young woman and goes to Romano's house begging him to perform the surgery.

In order to get her patient to tell her the location of a missing body, Corday agrees to grant him a fatal wish. Kovac befriends two brothers. He tells Weaver that his wife and children died in the Bosnian war. Former medical student Deb Chen returns to County General as a resident, using her Chinese name, Jing-Mei Chen.

Lucy's patient finally gets the call to receive a heart transplant, but there are complications. Greene interferes in a gay couple's domestic situation. Corday tricked her patient who murdered several women and now he's being transferred to a county jail.

Two boys brought in after a fight at school leads Cleo to discover that one of them has a number of bruises and infected wounds. Hathaway's obstetrics nurse, Abby Lockhart, joins the ER as a third year medical student on an ER rotation.

Dr. Greene and Dr. Corday bond with their parents, Lucy cares for a patient with a psychotic break, and Valentine's Day celebrations in the ER end tragically.

Carter and Lucy are discovered and the staff struggles to save them and go on with normal patient care.

Kovac witnesses an accident and saves the young victim's life. Carter slowly recovers from his brutal attack and undergoes excruciating physical therapy. Hathaway helps two sexually active 14-year-old girls.

Even though he suffers from intense pain due to his stabbing injuries, Carter returns to work and prescribes a controversial procedure for a suicidal patient. Greene tries to convince his father to undergo cancer treatment.

Chen's patient refuses to reveal to his daughter that she might have inherited a terrible disease from him. Weaver defies Romano's authority and performs a procedure that gets her suspended. An available kidney causes friction between Corday and Kovac as they decide which one of their patients will get it.

After Corday refuses to perform exploratory surgery on Cleo's patient, Cleo enlists Benton's help, infuriating Corday. Abby cares for a pregnant woman with five children who wants an abortion. Greene lovingly tends to his dying father at home.

Carter seeks psychiatric help because he can't sleep. He then visits the wife of his attacker. Weaver returns to work after her suspension. Hathaway and Kovac share a kiss.

Weaver reprimands Carter for doing a dangerous procedure without consulting Kovac. She also talks to Hathaway about Hathaway's lack of focus on the job. And while treating a 6-year-old patient involved in a minor car accident, Malucci and Cleo discover the girl has been sexually molested recently by her father.

Greene prepares to bury his father. Chen worries about Carter's mood swings. After witnessing the interaction between a dying woman and her family, Hathaway realizes she wants her family together and flies to Seattle to join Ross.

As the result of a school shooting, Kovac and Benton care for the gunman and his victims. Abby discovers that Carter has been illegally injecting pain relievers. Greene and Weaver confront Carter about his problem, and Weaver orders him to enter a drug rehabilitation center or leave the hospital permanently.

Dr. Carter struggles with his drug dependency; a custodial strike leaves the ER cluttered with garbage; a riot at a high-school football game leaves several wounded.

A young couple cope with their baby being premature; Greene and Corday struggle with their relationship.

Dr. Carter is allowed a cautious restart with small steps. An extremely blond Dr. Malucci is very curious who's made Dr. Chen pregnant. Dr. Benton has been written out of all the hospital's systems and is stunned by Dr. Romano. An unfortunate incident at a Science Fiction convention makes it look like scenes from the movie 'Mars Attacks'.

Benton is unable to find a job after Romano negatively influences local hospitals. He reluctantly agrees to accept Romano's demeaning offer of a per diem job at County with no benefits. Kovac and Abby are attacked by a mugger with a steel pipe. Injured, Kovac protects Abby and smashes the robber's head on the ground repeatedly.

Greene flies in a helicopter to a remote area of Indiana to rescue a heart transplant patient. The helicopter develops problems, and Greene arranges for paramedics to transport the patient to County. Because Weaver is gone for the day, Romano appoints Benton in charge of the ER. Kovac is plagued by the death of the mugger.

Dr. Corday suggests a quick surgical procedure for a patient with back pain before taking off on a romantic weekend with Dr. Greene. Abby's mother, Maggie, unexpectedly visits the hospital and wreaks havoc on Abby's life. Dr. Chen needs the father of her baby to sign paperwork to go through with the adoption.

Abby's mother decides to stay in town; Carter attempts to find a drug addict who left the hospital: Greene discovers his health is failing.

Maggie's emotional instability worsens. She refuses her medication, becomes combative and flees the hospital. Abby finds solace with Kovac. The gang member girlfriend of Benton's deceased nephew knows who killed the dead boy who was hated for his antigang stance.

Chen gives birth, but insists on breastfeeding the infant before she gives it to the adoptive parents. Greene and Corday consult a brain specialist in New York City who believes the tumor can be safely removed. Stressed and tired, Carter impulsively swallows two painkiller pills but intentionally vomits them. He confesses to Abby.

Mark Green is in New York on New Years eve for cancer surgery. Meanwhile a father and son are involved in a car crash.

Benton and Cleo clash over his deceased nephew's girlfriend. They finally agree to call a social worker. Benton confesses his love to Cleo. The spinal surgery malpractice suit is settled by employing a technicality: the equipment used was later recalled by the manufacturer. But Corday now doubts her abilities as a surgeon.

Greene returns to work but confuses words and displays uncharacteristic anger. Eager to get out of his per diem situation, Benton agrees to a full-time position. Carter visits his cousin, who became paralyzed after a drug overdose. A workplace disaster results in numerous injuries and fatalities among illegal immigrants.

Weaver becomes concerned about Greene's cognitive skills and surreptitiously calls for an official evaluation of his competency. Corday plans her wedding to Greene. Bishop Stewart returns, and Kovac realizes the man has a terrible disease. Dateless for a charity function, Carter invites Abby to attend with him.

As the new director of diversity, Benton studies medical school applications and discovers that his own academic record did not qualify him--he was admitted because of affirmative action. Weaver feels uncomfortable amongst Legaspi's lesbian friends. Carter treats an unvaccinated child who contracted measles.

In the series' 150th episode, a massive train wreck mobilizes the emergency room doctors. Corday, Carter and Kovac rush to the scene. Corday falls and injures her back, bringing on contractions in only her 25th week of pregnancy. While amputating the legs of a fallen firefighter, Corday stops because of her pain.

Weaver fears for her own reputation when Legaspi is accused of sexual harassment. Afraid to reveal her relationship with Legaspi--for both personal and professional reasons--Weaver fails to support her during the investigation. An infant is abducted from the hospital and later found on a train platform.

A demented patient causes a shootout in the emergency room. After terrorizing people in the ER with a gun, she gets shot by a policeman. She soon dies. Benton later discover her dementia was caused by an aftereffect of his surgery that he and Cleo should have detected. Carter pursues a cute intern.

Numerous mishaps threaten to mar Corday and Greene's wedding day. As the very pregnant Corday becomes increasingly agitated, the presence of her bickering divorced parents does little to improve her mood. With the intense rain, Greene has a difficult time making it to the church. But, evenutally, he arrives and they joyfully wed.

Abby and Carter travel to Oklahoma to rescue Abby's mentally ill mother and bring her back to Chicago. In Chicago, Maggie suffers from a sleeping pills overdose. At County General, Kovac frantically revives her. Benton treats a college student injured in a fraternity prank.

Maggie contests Abby's attempt to institutionalize her. Weaver treats a few bizarre patients. When Legaspi returns to work after being exonerated of sexual harassment, Weaver tries to reconcile with her. Benton injures his hand while transporting his former teacher to the hospital and must contend with the teacher's wisecracking elderly buddies (TOM BOSLEY and TOM POSTON).

Cleo and Carla clash after Reese gets hurt while in Cleo's care. Weaver and Kovac cannot save the life of a developmentally challenged woman's only caregiver. Abby goes to a therapy session with Maggie. Later, Abby confesses to Maggie that she is afraid to bear children because they might be bipolar like her mother.

The ER is flooded with foster care home residents, attacked by a shooter bent on tracking down his son, who , with the help of Dr. Green, was put into the foster care system amid allegations he was being abused by his father.

Weaver returns to the emergency room after a self-imposed sabbatical of three weeks, wondering how her newfound lesbian identity will affect her workplace relationships. Having purposely allowed a mass murderer to die, Greene must keep the secret amidst the scrutiny of his superiors.

Carter is overwhelmed by patients from a rock concert riot. Benton's former girlfriend and Reece's mother is killed in a car accident. Newly promoted to chief resident, Chen panics and misdiagnoses a patient. Kovac angers Abby by flirting with a waitress.

Greene's daughter comes to live with him and Corday. Carter and Abby become more intimate. Chen must prove her skills while saving a baby. Weaver terminates Malucci after witnessing him having sex in an ambulance.

Dr. Susan Lewis arrives, looking for work in the Chicago area again. Greene hires her, over Weaver's objection. Chen nervously attends a risk management review, accompanied by the unforgiving Weaver, to discuss a patient who recently died under Chen's supervision.

Lewis faces a hectic first day back at County General. Benton and Roger become frantic when they can't locate Reese. Carter's grandmother is brought to the emergency room. Carter and Abby deal with inept medical students.

Corday's ordeal, caused by the recent infection-related deaths of several of her patients, worsens when she is closely observed by a stern taskmaster. Corday is outraged when a county investigator accuses her of deliberately euthanizing the patients, who all happened to be elderly.

A new medical student, Michael Gallant, arrives in the ER. He's supposed to be working under Dr. Carter's supervision but John's grandmother is unwell. Elizabeth Corday is convinced that other doctors are refusing to work with her as a result of the mysterious deaths. Mark Green thinks she's overreacting but she's determined to find out what happened to her patients. Abby and Luka argue over the attention he is paying to a trainee nurse's aide. Dr. Benton finds himself in court to retain custody of his son, Reese. Carter and Susan Lewis treat a young woman who is both a law and a medical student. Green has to collect his daughter at school when she is suspended.

When a torrential rainstorm pounds Chicago, patients deluge the emergency room while Weaver speeds to an accident site. There, she finds a pregnant woman, Vicki, lying injured inside a wrecked ambulance while live power lines spark. Fourth-year student Michael Gallant makes a dangerous decision in order to help.

Peter Benton continues his court fight against Reese's stepfather, Roger, who seems to have the upper hand. When a woman is accidentally shot during a gas station robbery, Dr. Corday tries to convince the husband to let them harvest her organs. A 15 year old boxer is brought in with a head trauma after sparring with his older brother. Newlyweds are having trouble when she constantly breaks out in a rash; Carter thinks he knows the cause. Luka tells Abby that he may marry Nicole, who has told him she is pregnant. Dr. Green lays down the law when the police bring in a high school student and he learns that his daughter is outside sitting in the police car.

Dr. Benton is awarded full custody and Roger receives visitation every other weekend.

Abby helps a distraught boy whose mother died of a stroke; a man with schizophrenia, who once stabbed Carter and killed a doctor, is brought into the ER.

An injured and condemned murderer wants to die in the ER rather than await execution; Abby advises a neighbor to seek shelter from her abusive husband.

An accidental overdose brings Drs. Green and Corday's baby into the ER.

Greene confronts Corday when she orders Rachel out of their home; Abby tries to protect a battered neighbor who refuses to press charges against her husband.

After Dr. Corday moves out, Dr. Green fights loneliness and pain by immersing himself into his work. Dr. Chen discovers that a comatose teen is ready to give birth.

After some staff members are caught going through a dominatrix's bag, Weaver makes them attend a sexual harassment seminar, where they learn about each other.

Drs. Corday and Greene are awkward when working together in the ER. Dr. Weaver treats victims of an intense fire that may take the life of a dear friend.

As Dr. Greene's brain tumor begins affecting his coordination, he becomes concerned that his fate will be similar to the terminally ill patients he treats.

When Dr. Lewis gets a hysterical call from her niece, Susie, she hurries to New York to search for the child and her sister Chloe.

Dr. Carter reads a letter from terminally ill Dr. Green to the ER staff. Dr. Weaver lashes out at a mentally challenged patient. A terminal, homeless man continues asking for Dr. Green.

Dr. Greene's final days are spent in Hawaii with Rachel, teaching her to drive and surf. When he suffers a seizure, Elizabeth is called. Mark refuses to go home. He manages to make amends with his daughter before his eventual death.

Just when the ER is understaffed and swamped, two children who were brought in turn out to have full blown smallpox. The entire ER must be locked down. The staff needs to improvise while they battle not only the disease but also frayed tempers.

Casualties of a disaster flood the ER, which is short-handed because everyone is at Dr. Carter's going-away party because he's leaving the ER after 11 years. Dr. Pratt looks for the courage to confront his father, Charlie.

When a thirteen-year-old gymnast is brought into the hospital after having supposedly fallen off a wall, Dr. Banfield and Dr. Gates must sort out whether abuse is involved.

Trying to rescue a three-year-old girl from drowning in a nearby lake, Banfield is reminded of her own experience at County with Dr. Greene caring for her son.

Dr. Greene's final days are spent in Hawaii with Rachel, teaching her to drive and surf. When he suffers a seizure, Elizabeth is called. Mark refuses to go home. He manages to make amends with his daughter before his eventual death.

As Dr. Greene's brain tumor begins affecting his coordination, he becomes concerned that his fate will be similar to the terminally ill patients he treats.

Mark has to work for the fourth night in a row while a lot of the staff are absent and the number of patients is towering.

Mark rushes out to San Diego when his mother has a serious fall and is hospitalized. When he gets there he finds her suffering from mild dementia and questions the care she is receiving. To his surprise Cynthia Hooper follows him unannounced and uninvited, leading his parents to form a conclusion about their relationship. Mark also learns a lot about his parents' relationship and while he continues to struggle with his difficult relationship with his father, he also learns of some of the sacrifices the man made for his family.

Trying to rescue a three-year-old girl from drowning in a nearby lake, Banfield is reminded of her own experience at County with Dr. Greene caring for her son.

Dr. Benton has to deal with the aftermath of his mother's fall and crosses the line with the surgical attending when he insists on scrubbing in for her operation. Dr. Greene deals with Jodi O'Brien who is two weeks away from giving birth. With the obstetrics attending unavailable, he decides to try to deliver her baby in the ER, with tragic results.

After Dr. Corday moves out, Dr. Green fights loneliness and pain by immersing himself into his work. Dr. Chen discovers that a comatose teen is ready to give birth.

Weaver reprimands Carter for doing a dangerous procedure without consulting Kovac. She also talks to Hathaway about Hathaway's lack of focus on the job. And while treating a 6-year-old patient involved in a minor car accident, Malucci and Cleo discover the girl has been sexually molested recently by her father.

Benton has to attend a banquet at Vucelich's home and asks Jeanie to go with him. Mark hesitates to tell Rachel about the divorce.

Maggie's emotional instability worsens. She refuses her medication, becomes combative and flees the hospital. Abby finds solace with Kovac. The gang member girlfriend of Benton's deceased nephew knows who killed the dead boy who was hated for his antigang stance.