Sully and Maggie reconnect; Bobby visits his brother Matty and tries to prepare him for his release from prison; Sunny asks Kim for a place to stay and runs away when Kim refers her to a shelter; Carlos hits a pedestrian with the bus; Faith and Bosco investigate a grave robbery and ponder immortality; Jimmy rescues a new recruit who is trapped under a collapsed ceiling in an apartment fire; Bobby takes Doc's advice and tells Kim how he feels, only to learn that Kim feels she isn't good enough for him; Sunny ODs and Bobby helps a saddened Kim find out her real name and hometown so that her parents can be notified; Sully's approach to ""problem solving"" goes horribly awry in a domestic dispute; Carlos and Doc come to blows over Doc's training methods, forcing Morales to break them up; Sully learns that Ty has good instincts, enabling them to save a teenage girl from a sexual predator.

Ty is worried about Sully's dating Maggie; Faith and Bosco lose a witness who turns out to be the perp in a homicide; Bobby prepares for Matty's release from prison; while driving the bus, Carlos collides with a pregnant driver and later attempts to revive the baby she delivered prematurely after Sarah pronounces it dead, unaware of the consequences for the parents; Jimmy rescues a boy from a tree; Bosco and Ty take issue with Sully over his handling of a belligerent collar.

On Thanksgiving Day, Bosco tries to resolve a family conflict in a restaurant while Faith deals with the same thing in her own home. Bobby's mother refuses to allow Matty to attend the family's holiday celebrations, and leaves it up to Bobby to tell his brother. After a shooting, Ty and Sully disagree over how they should report the incident to their superiors and the investigating team.

An explosion in a building about to be demolished leaves men trapped inside, forcing the firefighters to make terrible choices; Fred's drinking problem escalates; Doc cancels his date with Brenda.

Jimmy's failure to watch the firehouse door leads to tragedy; Morales, devastated by the loss of a young patient, reaches out to Doc for consolation; Sully's first partner commits suicide, prompting him to seek out Maggie and reflect on where his life has gone; Bosco tries to buy a '67 GTO from a homeless man; and Bobby continues to do whatever he can to get his mother to reconcile with his brother.

Faith, Bosco, Sully, Ty and Candyman race through the neighborhood on foot in pursuit of a trio of Uzi-armed thieves; Candyman risks his life to save Ty; Bosco's cold refusal to get medical assistance for one of the perps leads to the robber's death; Ty searches for the truth about his father; Bobby's mother tells the police where to find Matty, who desperately pleads with Bobby to give him some getaway money; Bobby agrees, but begs Matty to turn himself in; Matty gets high and takes off, leaving Bobby crushed and seeking consolation from Kim; and Carlos finds out about Doc and Morales.

It's Valentine's Day and Bobby and Kim have spent the night together; Bobby's confession of love leads Kim to realize that they've made a big mistake; after agonizing all day, she finally confesses and breaks Bobby's heart; seeking solace in a bottle, Bobby finds himself at a local bar next to a woman who has also been jilted that day, and they go off to her place; Fred drunkenly totals the car on the way to pick up Emily and Charlie; Faith arrests him and refuses to bail him out; when he finally arrives home, Faith has his things already packed and throws him out; Carlos tends to a girl who runs into a bus and then falls for him; the gay community is targeted by a gunman and a vigilante group forms to find the killer; Ty arrests a girl for auto theft who turns out to be Malcolm's sister; and Faith lets Bosco know that she is fed up with his bigotry.

Davis rescues a drowning newscaster from a downed helicopter, and the ensuing rush of media coverage on his heroism brings a strange young woman to meet him. She turns out to be his half-sister, and Davis uncovers secrets about his father's second family. The turmoil from the revelations causes disturbances between Davis and nearly everyone close to him. Meanwhile, someone's throwing bricks at random citizens, putting everyone in the city on edge.

The police officers sort through the carnage and count their dead in the wake of a shootout between rival gangs. While Faith tries to interrogate Fyodor Chevchenko, a ruthless Russian mob boss, Sully worries about the severely wounded Ty and regrets causing the incident. Tatiana chastises Sully for hassling her injured son. Faith worries about Gusler, her ineffective, frightened rookie partner and a weary Doc gets some unexpected, good news about his medical malpractice suit.

On his last day on the street, Doc's guilt and grief over Alex's death emerges as anger towards everyone he encounters, especially Eugene, the new paramedic trainee whose place Alex took the day she died; Kim becomes frantic as she fears that she have been exposed to HIV after having unprotected sex with a drug addicted Noble, and Jimmy agrees to accompany her when she gets tested; Swersky goes to bat for Faith by creating the opportunity for Bosco to talk to her before she's interrogated by I.A.B.; Carlos is less than thrilled when he discovers that Kim is the new supervising paramedic and Jimmy has been promoted to take over Lt. Johnson's position; Bosco returns to work and faces a hostile reception from the squad for ratting out Maritza; Faith awakes to discover that she's paralyzed; Maritza refuses to let Faith off the hook for shooting her until Bosco tricks her into recanting her story; Faith thanks Bosco for keeping her out of jail and saving her job, and then tells him to get l