Emmy nominee Bob Newhart guests as Ben Hollander, a distraught architect whose degenerating eyesight causes him to be despondent while a spirited new nurse, Samantha Taggart, joins the staff. Elsewhere, disaster strikes when the doctors suspect a mother is abusing her child while Dr. Corday learns something shocking about the charismatic Dr. Dorset, and Dr. Archie Morris is overwhelmed by the chaos and grisly conditions of life in the E.R.

Pratt and Kovac clash over a miscarriage-prone young woman who arrives to deliver a premature baby. Pratt wants to make heroic efforts to save the unborn child, while Kovac is adamantly against spending vast amounts of money to keep the forever sickly baby alive.

To everyone's amazement, Lewis makes a date to share a home-cooked dinner with the elderly Ben Hollander, her depressed patient who is going blind.

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

Neela helps treat two Amish teens who were in a car crash. Sam argues with Dr. Kovac when he pays too much attention to her son.

Carter returns from Africa full of surprises including a new love, Makemba ("Kem"). Pratt accidentally breaks a patient's neck while doing an unsupervised intubation. A whole nursing shift cannot go home until they find one missing Valium.

Sam treats an abused, pregnant teen. Dr. Carter introduces African girlfriend Makemba to wintertime. ER chaos shocks a risk-assessment expert. Dr. Pratt and Abby restrain a man who has tuberculosis.

Carter misses his pregnant girlfriend who has returned to Africa. A family of four is rushed to the emergency room after suffering carbon monoxide poisoning from their faulty furnace--forcing the claustrophobic Neela to accompany a newborn baby into an extremely uncomfortable hyperbaric chamber.

Dr Morris agitates a patient who then leaves, steals a tank, and rampages through Chicago on his way to County General. He makes it all the way to the ambulance bay before the CPD finally stops him. Sam tries to figure out her relationship with Kovac while Gillian shows up at the ER to cement plans for dinner with Carter, Kem and Kovac - making things that much more difficult. Neela confronts Frank about his arrogant bigotry, bluntly telling him she wants nothing from him but silence from this point forward. During the initial onrush of patients due to the tank rampage, Frank has a heart attack which is, thankfully, caught. Frank's wife and daughter show up and are rushed up to the cath lab where Dr. Pratt is helping Dr. Kayson keep Frank alive. In the end, Neela winds up in the family room with Frank's family listening to them describe a side of Frank that no one has ever seen. Meanwhile Kovac treats a 13 year old with chlamydia and counsels him to contact his sexual partner - which turns out to be quite a few teenage girls.

Carter defends his protégé Neela when Weaver and other doctors rate the residents. Carter urges his student to be more proactive in the emergency room, but Neela goes too far in treating a patient with a brain injury--and sympathetic Gallant errs further by falsifying a medical report. Meanwhile, Chuck protects pregnant Lewis from a pervert who is harassing her. Kovac treats a disoriented young boy whose dad fears that tests will reveal he is not the boy's biological father. Chen is unable to find a caretaker for her combative father. And Corday is uneasy about dating two men at once.

Weaver rushes to the aid of her wife, 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.

Pratt struggles to diagnose a woman who suffers mysterious chronic seizures. An attractive woman, Campbell, informally accuses flirtatious Pratt of sexual harassment. Abby ponders how to get her contentious patients' attention during her psychiatric department rotation.

Carter takes Kem to the hospital to check on their baby since it's not kicking anymore.

Kovacs stops to help a woman and her son whose car broke down. Steve is getting close to Alex, and Sam panics. Abby is looking for her letter whether to see she passed her boards. Pratt shows off his new Chrysler. Elgin tries to build a connection between him and Pratt. Jing-Mei might be battered by her senile father.

After being shot at, Pratt, Jing-Mei and Elgin are trying to get out of their sinking car. Sam took Alex with her while fleeing from Steve. Kovac is considering going after them. Abby wants to go to bed since tomorrow is her first day as a doctor, but is thwarted by Weaver, whose custody battle might take a dramatic turn. A young drug dealer is brought in with "a foreign object" in her tunnel of life.

Neela is still struggling with her decision not to continue becoming a doctor. We discover that Ray is in a band. Kovac and Sam are in love, but where does that leave them?

It's a busy Fourth of July and Carter is the only attending working.

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

A wounded police officer's teenage son must make a life or death decision. Abby tries to convince a girl needing appendicitis surgery's parents not to transfer her and do the operation at County, but her father wants her transferred to another hospital due to his own trauma with surgery complications from years before.

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.

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.