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.

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

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.

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.

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.

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.

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.

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.

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 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.

Jeanie fears Scott Anspaugh's cancer may have returned. Hathaway learns a disturbing secret about a 16-year-old girl. A pregnant patient fears she'll miscarry; Morgenstern returns to work, but perhaps too soon after his heart attack.

Carter finally works up enough nerve to ask Del Amico out. Jeanie tries to help Scotty decide whether to undergo an experimental treatment and Benton takes unexpected action during an operation with Morgenstern.

Del Amico, Ross and Corday confront disturbing situations after the bombing of a women's clinic. Benton comes under review for controversial actions in the OR. Jeanie endures one of the most difficult days of her life as she says goodbye to a friend.

Ross treats a 6-month-old recovering from methadone withdrawal. A televangelist and his wife, who's suffering from an infection, plan a broadcast from the ER. Del Amico's old boyfriend arrives, and Jeanie fears her health is rapidly declining.

Ross and Hathaway's jobs are in jeopardy after their unauthorized treatment of a drug-addicted 7-month-old boy is discovered. Corday loses her sponsorship. Carter suspects Del Amico's boyfriend when drugs are stolen.

Dr. Corday's father visits from overseas in an attempt to convince her to join his medical practice. Weaver suggests that Elizabeth look into alternative methods to stay in America, like starting over as an intern. Weaver also doesn't let an opportunity pass to remind Doug of the way he bypassed her authority in the McLean case. Lucy continues learning, earning more of Carter's respect than she deserves. Peter takes Reese in for another hearing test. Mark has several discussions with paramedics about the state of the EMT program. Carol hires a nurse practitioner to help out in the clinic. Carter is having trouble being an RA in the dorms.

Mark goes to a trauma scene with the EMTs, where he treats a gunshot victim who has a bomb strapped to himself. Later, Mark’s daughter persuades him to treat a horse with colic, and Jerry gets the bad end of the enema. Carter intubates an elderly woman who is DNR. When her HMO declines to admit her, Carter either has to find a relative quickly or let her die. Kerry finds herself more and more frustrated when Anspaugh suggests that they're not considering her for ER Chief, and she discovers she’s the last to hear that Doug was made a pediatric attending. Corday serves her last day as a surgical fellow. Benton meets with Carla to discuss getting Reese hearing aids. Jeanie returns from vacation. Carter goes out with Roxanne, the insurance saleswoman he treated.

Dr. Corday begins her first day as an intern, first by being assigned to Dale Edson, then being treated as Romano's lapdog. Kerry is interviewed for ER chief. Doug and Carol ponder parenthood when Carol realizes she may be pregnant. Carol and Lynette try to keep a wounded gang-banger from leaving and seeking retaliation. Lucy faces the wrath of Carter when he discovers that she doesn't know how to start an IV. Jeanie asks Doug if she can be a full-time PA for the pediatric ER.

After Mark saves a 16-year-old assault victim in a daring rescue, he tries to convince the boy to leave the streets for a shelter. Carter loses his beard when two carpet installers come in covered with glue. Peter consults a deaf physician regarding Reese's hearing condition. Corday is reassigned as Benton's intern. Kerry hears more discouraging news regarding her bid for ER chief. Carter loses his RA job, forcing him to go apartment hunting. He finds one--in Weaver's basement.

Dr. Corday commits a deadly error after being on-call for nearly 36 hours straight. Peter visits Dr. Kotlowitz and receives encouragement regarding a cochlear implant for Reese. Dr. Amanda Lee, a prospective new ER chief, visits. In the wake of a failed pregnancy attempt, Carol lashes out at a mother using abortion as a means of selective birth control. Carter and Lucy feud when Carter accidentally uses her palm computer and finds out what she thinks of him. Mark panics during a paramedic initation.

Carter and Lucy scramble across Chicago to find a dying girl's father who's a perfect match for her very rare blood type. Benton operates without transfusions to save the little girl's life.

Carter plays tour guide for Ruth Johnson, who was born in the hospital 100 years ago to the day, and her large family. Carol treats a boy who was hit by a car and tells a story of being chased, his friend being shot in the process. Peter observes Kotlowitz install a cochlear implant and decides to wait before scheduling an operation for Reese. Mark dines with Dr. Lee, new ER chief. Dr. Corday proposes radical changes in scheduling at an M&M conference, and later decides to break off her relationship with Benton.

Amanda Lee's obsession with Dr. Greene comes to a head when Mark inadvertantly digs up old med school records damaging to her career. Carter tries to save Lucy from Edson's advances. Peter treats Dr. Parks' grandchild, who interprets for her deaf mother and grandmother. Police officer Reggie Moore asks Jeanie out. Kerry receives a call from someone claiming to be her mother. Doug receives a job offer from Portland.

Doug jeopardizes future federal grants for the entire ER when he breaks a double blind study by giving a sample drug to an ailing patient. Doyle lodges a sexual harassment complaint against Romano, hoping Dr. Corday will lend support. Lucy begins her surgery rotation under Benton's tutelage. The two of them treat a man claiming to be 140-years-old. Mark declines to proceed in the NASA program. Carol questions Lynette's intentions when she hosts a women's health clinic for African American women only. Mark goes to bat for Pickman when she inadvertently leaves a severely injured man at an accident scene.

Ricky Abbott returns to the ER. Doug forges papers to allow Joi to treat Ricky at home. Corday decides to back out of the Romano sexual harassment investigation after he threatens to expose her relationship with Benton. Romano is later named Acting Chief of the ER. Dr. Greene treats a Nigerian janitor for back pain and impotency. Carol and the nurses watch a bunch of dogs when their owner is hospitalized. Carter diagnoses a med student with Hodgkin's disease. Kerry initiates a search for her biological parents.

Doug faces possible criminal charges after Ricky Abbott dies when Ross bypasses system lockouts to enable Joi to give Ricky a lethal dosage of dilaudin. 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 tampering with the double blind study. Carter and Lucy discover a mutual attraction. Benton studies with a sign language instructor.

Greene assists paramedics in treating injured children at a school bus accident. En route, Doug and Jeanie survive their own accident. Kerry stops Doug from treating Jeanie...or any other patient. Doug decides to resign and leave Chicago for the Northwest and asks Carol to come with him. She decides against it, but he leaves anyway. Carol steps down from running the clinic so that Anspaugh will keep it open. Jeanie discovers she may have contracted hepatitis. Hospital janitor Mobalage's wife is stabbed.

During a paramedic ride-along, Carter is forced to drive the ambulance while fleeing a riot scene and inadvertently runs over a teenage boy. Later, a paramedic is shot by an angry mob looking for the driver of the ambulance. Carol is despondent following Doug's departure. She later discloses that she's pregnant. Kerry is intrigued by an injured pro wrestler and his relationship with his father. Lucy tangles with an Asian family that requests their matriarch not be told of a cancerous tumor. Jeanie turns down dates with both Dr. Baker and Reggie, telling each she's seeing someone else.

Romano forces Benton to choose between the trauma and cardiothoracic fellowships. Carol worries that she may have lost her child. Corday and Greene bond on the way to a medical conference. Carter mentors an aspiring teenager. Lucy, on a psychiatry rotation, treats an overmedicated foster child. Jeanie finds her faith while treating a reverend.

The ER docs tend to three teenagers who were in an accident on the way to their senior prom. Greene and Carter treat the most severely injured, a boy suffering from third degree burns over 80% of his body. Benton receives the ER trauma fellowship. Carol finally tells Doug about her pregnancy; Kerry also figures it out. Mark and Elizabeth draw closer. Lucy tells Carter about her Ritalin addiction. "FBI agents" bring in a shot stripper.

Carol's pregnancy becomes public knowledge as she learns that she's having twins. Lucy has problems trying to go off Ritalin. Peter learns Carla plans to move to Germany. Kerry finds an abandoned youngster and brings him to the ER. Mark and Elizabeth discuss their relationship. Jeanie and Reggie draw closer again.

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.

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.

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.

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

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.

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.

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.

Dr. Carter, Abby and other staff of the ER are quarantined as the CDC investigate a mysterious, deadly outbreak.

Dr. Pratt brings a gun into the ER; Dr. Weaver tries to conceal her pregnancy; a woman plots against her dying husband; Dr. Chen treats math students who overdosed on an unknown stimulant.

Abby's troubled brother is missing. A car runs into a crowd of teen girls. The alderman with syphilis gives Dr. Weaver a promotion. Dr. Lewis looks forward to a blind date.

Dr. Weaver bends the rules and treats the Alderman's lover for syphilis. Dr. Kovac's patient claims she was sexually abused at a boot camp for troubled youth. Dr. Carter treats a women with a nasty personality.

On Thanksgiving Day, a helicopter crash outside the ER leaves several injured, and kills Dr. Romano. Alex tries to bring Sam and Luka together.

Weaver rushes to the aid of her female life partner, Sandy Lopez, when the firefighter is severely injured while working and must now battle for her life. Frightened Weaver whispers hope to Sandy by reminding the victim of their newborn child.

Carter, Pratt, Kovac and Abby are dealing with a woman and her three children who've jumped from a three floor apartment trying to escape from the father. Meanwhile Dr. Lewis becomes Chief of Emergency Medicine, Howard quits his internship and Dr. Corday is facing dismissal.

Sam's ex-husband shows up and wants to take Alex on a trip. Gallant is back and Neela hopes to see him before he goes back to Iraq.

Jules 'Ruby' Rubadoux is back in the ER. He's still angry with Carter about the death of his wife.

Dr. Nate Lennox, a former professor with ALS, is brought in as the progression of his disease is chronicled through his own flashbacks as he is treated by each of the doctors at one point. As Lennox wants to give up, Abby fights to convince him to keep on fighting.

Chaos reigns in the ER when two prisoners are brought in for treatment, but instead plot a violent escape. Their desperate actions place one doctor in harm's way, and forces one nurse to become a tool in their plan.

As Abby and Luka cope with their newborn's life and death struggle, the couple is shocked to receive a surprise visitor: Abby's mother Maggie. Meanwhile, Sam fears the prospect of criminal charges; Neela discovers that Tony Gates will be joining the ER team as an intern and Morris gets his job back while Weaver gets demoted.

In 12 hours, the ER will shut down. As Kovac is under pressure to take care of the patients before the final hours, he makes a pivotal decision about his future. Meanwhile, Sam befriends a photojournalist who returns only this time she's terminally ill; Pratt is concerned when his brother ends up in the ER drunk; Morris confronts Gates when he ignores his orders and angrily sends him home while Gates tries to defend his actions.

Moretti begins to make his presence felt, as he implements changes in the way patients are seen. The ER staff differ on how procedure when a patient comes in with a bullet in him needed as evidence. Neela finds herself the object of more attention that she wants, or needs. Abby had passport woes, and struggles with the changes being made. Pratt and Morris find themselves forced to defend their actions, Hope prepares for a new mission, and Gates finds himself labeled the reject in his new assignment.

It's time for changes at the ER when Anspaugh makes an unpopular decision. Abby has old demons to fight with, which distance her from friends and family. Even Luka seems to be at a loss to help Abby. Love is in the air when a secret romance blooms between two doctors.

After being passed over for Chief of the ER, Pratt is looking for a hospital that will appreciate his talents. A former employee of the ER brings her sick son in for tests. Neela's cousin is in town for a visit, and Morris and Harold compete for her affections.

Abby is back from rehab and finds herself the object of scrutiny. She confesses to Pratt that Luka might stay in Croatia longer than planned. Harold seems to have won over Neela's cousin. Multiple victims from a fire fill the ER.

Kovac is in Chicago looking for hospice-care work. Neela's aorta surgery has caused an infection in her patient. Abby treats a teen who has been beaten up. Brenner continues to cause problems for the ER staff.

When a drunk patient is admitted to the ER, his actions endanger everyone at County. Pratt is still pursuing his dreams of becoming Chief of the ER, and Gates is worried about his future with Sam. Luka unexpectedly runs into Dr. Moretti.