Pratt, Chen and Elgin fight for their lives after the car they are in careens into the Chicago river after a man opened fire on them. Sam tries to escape her boyfriend with Alex as Neela returns to the ER. Carter and Kem mourn the passing of their unborn child. New interns join the ER.
Carter has a hard time handling his departed girlfriend. Abby hits the ground running as a doctor, handling the case of a girl sold into sexual slavery. Kovac confesses his feelings to Sam. Neela has to face her parents after quitting her medical assignment elsewhere.
A brain dead biker's girlfriend hopes to donate his organs to a friend seeing as both have HIV. Ray feels betrayed when Abby orders a drug test on one of his patients. Pratt continues to have trouble adjusting. Corday questions Weaver's choice for surgeon, especially after not being consulted in the decision.
Two children come to the ER after taking a three story fall. A man's rash turns out to be an indication of cancer. Corday is punished for going ahead with an HIV-positive organ transplant operation. Lewis seeks Neela's return to the ER.
Neela returns to the ER and, as she, Abby and Ray compete over who can handle the most cases, Ray makes a critical error. Abby seeks Ray's help in obtaining AIDS medication for a patient. Carter makes advances towards Wendall.
A real-time episode focussing on a man who comes into the ER with complaints of stomach problems and learns, along with the staff, the situation is much more dire.
Sam and Kovac treat a woman who was savagely raped and severely injured, yet still fights to help the police. Lewis springs an emergency drill on the staff.
A police officer's son is forced to make a medical decision when his father ends up in a coma from a gunshot wound. Abby handles the case of a girl suffering from appendicitis.
Christmas Eve hits the ER and Abby tries to find a dialysis patient's doctor. Pratt visits Chen and learns more of the increasing toll exacted on her by taking care of her father through his declining health. Carter and Wendall share a holiday kiss.
While on a break outside, Abby is kidnapped at gunpoint and taken in an SUV by gang members who want her to treat one of their own wounded members. Meanwhile, Ray is hurt after a female patient he is treating requests a new doctor, but soon comes to learn the reason behind her decision.
Lewis tries to give patient satisfaction marks a boost by assigning Kovac to show the residents more effective methods of communication. The doctors are quickly forced to try out their communication skills when two teenagers afflicted with gunshot wounds are admitted, but after a rough surgery, Neela is unable to clearly tell one of the boys' grandmother of his death.
Carter tries to discern the reasons behind a teenage kidney transplant recipient's health problems and links them to a new drug. When Neela follows up on the internet, the drug company reacts. Abby and Neela are teamed up with Jake and Kovac, two men the ladies are crushing on.
Pratt looks to Wendall for help on a young boy's injuries. Kovac teams up with Pratt for a gunshot wound. Jake pushes Abby for a chance at a relationship.
Weaver comes face to face with her birth mother, but revealing that she is gay drives a wedge between the two as her mother is highly religious. Carter refuses to let the hospital be scammed out of painkillers by a couple looking to do just that.
Kovac and Sam attempt to save the life of a soccer mom after she suffers a stroke. Neela and Ray handle the cases of three neglected children. Carter faces the decision of moving forward with Wendall, but at the cost of his love in Africa.
Gallant tries to secure a young Iraqi girl treatment at County when she's wounded by a car bomb. Though separated by a great distance, the lives of Gallant and Neela prove to be eerily similar.
Neela learns of Gallant's return stateside accompanying a bombing victim. Sam's ex-husband creates trouble in her life. Pratt treats the young victim of gun misuse.
Neela, Sam and Lewis are confounded by a hunger strike victim who refuses food or medical assistance until her son's deportation case is re-examined. Abby worries that one of her elderly patients is being abused.
An elderly patient, Jules Rubadoux, accuses Carter of killing his wife a decade ago even as he's asked to go under for heart surgery. Pratt makes time with a social worker.
Morris starts off as Chief Resident by going up against Pratt in the wake of an apartment building fire. Lewis is upset about Carter's appointment over her.
Luka and Samantha go to a relationship counselor. Pratt confronts Neela for her treatment of a baby. Abby contends with a misdiagnosis that nearly kills an emphysema patient. Ray makes a costly accident with a stab victim. Carter meets up with Kem in Paris to comfort her about her mother's hospitalization, but realizes his love for her and vows to return to Africa to be by her side.
As Carter prepares for his departure from the ER, four new interns sign on. Ray is shaken by a disaster at a party he's attending, but finds resolve under the pressure and an understaffed ER is pushed to its limits. Pratt tries to visit his father.