Sam and Kovac search for Alex who they believe has fled in search of his father. Their worry is compounded by the fact that Alex is without his necessary insulin. Neela, Ray and Abby find their hands full with the new interns on staff.
Ray tries to help a woman who starts to give birth prematurely after a car accident. Pratt tries to confront both his father and his feelings. The relationship between Sam and Kovac continues to be in question.
A new nurse interferes with the standard running of the floor with her rules. Kovac and Sam have a tough time working through their personal issues on the job. Abby tries to help a woman work through her breast cancer.
Kovac handles a newly awoken coma patient who has lost nine years of her life. Abby helps Dubenko through some prostate cancer news. Nurse Manager Eve continues to implement her tough new system. Barnett spends time working the phones in toxicology. Neela believes a mother may have purposefully crashed her car with her baby on board.
Dr. Victor Clemente arrives at the ER but masquerades as a patient so he can get a handle on the doctors he'll be working with. Kovac becomes friendly with the woman formerly in a coma. Abby gets a mammogram on the say so of a breast cancer patient. Pratt's father works to gain forgiveness.
Dubenko continues to make his presence felt in the ER from home through a robotic proxy. Clemente, Neela and Abby secretly take care of a chimpanzee in the ER.
Neela expects to greet Gallant, home from Iraq, but gets a call from Iraq instead. Abby is caught between Kovac and Clemente when they butt heads over a patient's treatment. Neela faces a decision of conscience when the person responsible for a shootout that wounded both a young girl and a police officer comes under her care.
Neela and Gates arrive at a crash site and try to help those inside a burning building even as the people affected by the event flood into the ER. Dr. Gallant returns.
Gallant proposes to Neela and suggests that get married that day. To impress Weaver, Kovac and Clemente try to get along, almost too well. Sam contends with a mother hesitant to get her son proper medical attention.
Pratt and Weaver work to save a young girl from a gunshot wound. Nurse Haleh chooses a new choir soloist, Dr. Morris. Eve punches out an annoying Santa, pours urine on him and then gets fired for it. Abby has a big Christmas gift for Kovac.
Abby tries to decide whether or not she wants to be a mother with Kovac even as Neela and Kovac try to help a pregnant teen. Ray asks for time off to record with the band. Police come to the ER looking for Clemente.
Dubenko gets more than he bargained for when he picks up a day shift. Ray tends to his abused younger ex-girlfriend. Abby and Kovac go baby shopping. Neela gets positive word on a surgery elective program, but wonders about her marriage to Gallant. Morris frets over meeting a woman off the internet for a date.
Dr. Lennox, a medical professor whose path has crossed many of the staff, arrives at the ER with ALS and pneumonia and wants to give up the fight.
Clemente's time away from the hospital with Jodie comes to an abrupt and violent end. Pratt volunteers for a charity bachelor auction and the winning bidder is a man. As it turns out, a man bought the date for his female friend. The ER receives a postcard from Dr. Carter.
Carter works in the Sudanese desert area of Darfur. Pratt and Neela try to save the life of a teenage hit-and-run victim. Pratt comes to realize his direct ties to the crime.
A dangerous circumstance creates a possible threat for the entire hospital staff. Meanwhile, Kerry comes to grips with a complicated decision, while Neela tries to get herself some help, and Sam is given a tremendous opportunity by a patient.
Abby and Kovac try to assist a girl who has been brought in with stab wounds, but as she starts to slip, Clemente comes in and offers the possibility of a risky surgery which could save her. Meanwhile, Neela gives a speech to a surgeon’s convention which fares poorly, while Sam decides to take on another job to help her mounting costs and Ray gets the case of a suicidal man.
Luka gets a hostile reaction when he responds to a distress call. Sam begins to find happiness in a new approach to her life. Neela is stunned when some unexpected people appear in her life and she is hit with some surprising information. Meanwhile, Morris and Abby try to handle the complicated case of an auto crash victim.
Abby senses that something is not quite right when a grandmother and her 12 year-old grandaughter are brought into the ER. Sam's imprisoned ex-husband Steve is brought into the ER and all the doctors assume that he is faking, but when further tests prove otherwise, Steve finds his way to the operating table.
Pratt gets to work in Darfur, and soon finds his eyes opened to the need all around him. Debbie attempts to persuade Dakarai to seek treatment for his illness. Carter, Pratt and Dakarai find themselves in the middle of the conflict when a man and his pregnant wife arrive at the camp needing treatment, with trouble not far behind. Events force Pratt and Dakarai to make a dangerous journey.
Clemente’s behavior grows more and more erratic, forcing Luka to take a stand. Pratt returns from Africa, and works with Luka, Abby, and Sam on the case of a father and two sons who appear to have been beaten by gang members, but soon, Pratt learns the real story. Morris and Albright throw off some sparks. Dubenko has good news for Neela, but will two visitors bring something different?
In the aftermath of the tragedy befalling the ER, it’s an ordinary day with the usual collection of patients. But soon, the day becomes anything but ordinary as two prisoners intent on escape come to the ER for treatment, along with a hidden conspirator.