Yokas continues to have marital difficulties with Fred and, when she meets up with an old flame at the scene of a car accident, she finds herself very tempted to accept his invitation to meet him in his hotel room to catch up on old times. Doc's dad ends up in intensive care leaving Doc with some hard decisions. A perp accuses 'Candyman' of stealing money from him when he arrested him. Davis believes the criminal and is not sure how he is going to answer IAB's questions about what happened, even though he didn't see anything happen. The police station takes on the fire station in a basketball game.

Carlos falls behind in his studies and then hears some shocking news from Vangie; the cops search for a two-year old girl missing after her family is involved in a car crash; Bosco and Faith contend with a disabled man dealing drugs to children; Sully and Davis track down the alcoholic who attacked the pastor of Sully's church.

Doherty shows his bravery trying to save the mother of two young children from a fire. Meanwhile Bosco and Faith are out looking for the man suspected of starting the fire in the first place. Davis tries to set Sully up on a blind date and after her pimp beats up Malcolm's sister they try to find him before he kills the man who did it. Carlos' girlfriend problems escalate and Doc's relationship looks like going to the next stage.

Yokas and Bosco chase a carjacker into a multi-level garage. When the thief drives off the edge of the top level and crashes to the ground, Bobby risks his own life to save the driver. Much to the surprise of everyone who knows him, Bosco goes to the opera with Nicole and her parents. Carlos gets into trouble with his boss and Vangie. Sully and Ty go to help Candyman on a job, and Ty tells Candyman exactly what he thinks of him. Jimmy has news for Kim which surprises her, and annoys Bobby everytime Kim tries to talk to him about it.

Doc and Carlos are rescued by the firefighters when they get trapped in an eighteenth floor apartment with a patient who cannot walk; Ty comes to the end of his probationary period; Faith discovers that she's pregnant again; the firefighters come under fire from a madman when they arrive to fight a car fire.

The ordeals of an elderly friend prompt Sully to consider his own loneliness; Alex regrets revealing that she discovered Jimmy on the eve of his wedding having sex with an old flame who happens to be Lombardo's current girlfriend after the news spreads like wildfire throughout the squad; Jimmy and Brooke get married.

Bosco, Yokas, Sully and Davis search for a cop killer on the streets, and cope with an obnoxious new sergeant at the station house.

A secret threatens to destroy Jimmy's relationships at work and home; Sully makes a date with his pretty neighbor; Bosco gets violent after his mother is beaten by her boyfriend.

Faith, Bosco, Carlos and a wounded Doc find themselves trapped in an abandoned tunnel and unable to reach Central on their radios; the firefighters get into mischief during a long lull between calls; when the C.O. can't raise Bosco on the radio, Sully tries to cover for him.

Yokas and Bosco try to find a missing boy whose parents think has been taken by a registered sex offender; Sully prepares to be questioned about his wife's background

Doherty, riding on his motorcycle, is first to arrive at a multivehicle collision; Taylor is hit by a car; Tatiana goes to see Chevchenko, and tragedy ensues.

Chevchenko has Tatiana's son killed; Fred comes home from the hospital; and Davis gets a job offer.

Chevchenko has Tatiana's son killed; Fred comes home from the hospital; and Davis gets a job offer.

When a fire breaks out in the supermarket where Bosco and his mother Rose are doing some late night shopping, Bosco rescues most of the shoppers but cannot save a young mother when she goes back inside to retrieve her purse. After Jimmy tells him that the fire was probably deliberately set, Bosco is convinced that he saw the arsonist in the crowd outside after the fire. Sgt. Cruz gets Bosco and Faith assigned to the Anti-Crime Unit for a few days so that they can track the guy down. At the scene of another supermarket fire the next night, Faith takes down license plate numbers, Cruz photographs the crowd and cars at the scene, and Bosco nabs the man he saw in the crowd the night before. The man turns out to be a fire buff, but Faith and Cruz's work bears fruit and they find their arsonist -- the son of Doug Maple, an NYFD arson investigator. A depressed Sully is still on leave, drinking too much, and sleeping on the couch at Ty's and Carlos' apartment; Doc connects with an attractive

Emily discovers just what Faith's job entails and how much her mother loves her when they are taken hostage during a bank robbery, and Faith risks her life to save her daughter.

Monty and Joy hook up. Miguel witnesses one drug dealer murder another, and becomes the dealer's next target. On his first day back at work, Sully rides with Faith, who is put off by his short fuse and bad attitude. When he leaves a prisoner unguarded and uncuffed, Faith tells him to go home because he's not ready to be back on the job. Sully gets drunk and goes to his mother's nursing home. Sobbing about Tatiana, he tries to batter down the door when the receptionist won't let him in and calls the police. After Hancock arrives on the scene, Sully mouths off to him about Nancy in front of the other officers who are there to take him home.

Bosco is dismayed as he watches Cruz go to the extreme lengths of planting drugs, frightening children, and faking a dying declaration in their attempt to arrest the drug dealer who killed another dealer and then tried to to kill the 12 year old boy who witnessed the crime; Nancy tells Ty that she's ending her relationship with Hancock, and gives Ty the ammunition he needs to get out from under Hancock's thumb and back to duty at the 55, as well as getting Sully's suspension from duty lifted.

Doc supervises a new paramedic on her first day; Carlos is arrested after a teenaged patient accuses him of molesting her; Bosco and Faith search for an escaped prisoner; Sully and Davis team up with fire and EMS to save construction workers when their scaffold collapses; in the aftermath of the bank robbery, Faith is troubled when Emily asks her how many people she's killed in the line of duty.

Ty bails Carlos out and unsuccessfully tries to help him smooth things over with Nicole; after Bosco and Faith break up a domestic disturbance between an old friend of Faith's and her lover, Faith convinces her friend to leave the abusive relationship; Alex gets irritated when the other firefighters make fun of her brother; Sully continues to drink and have a poor attitude on the job; Jimmy is appalled when his face appears on a poster for an erectile dysfunction product, and is stunned when he discovers that the company paid the charity for whom he posed for the picture $10,000 for the right to use the picture, and that their website got 3,000 hits the first day from women wanting to know his name; when he discovers that everyone thinks that he's guilty and he's likely to lose his case, Carlos resigns in the hope that Nicole will drop the matter, and he'll be able to avoid a conviction that will end his visits with Kylie and his hopes of becoming a doctor.

Sully's stopped drinking, but his poor attitude remains; Carlos gives his two week notice; a blizzard blankets the city and the squads are called in early; an understaffed Doc defies orders and puts Carlos back on the street as the squads are kept busy rescuing victims of the storm; Faith's initial wariness about Emily's new boyfriend Eric turns out to be well-founded when he is brought into Mercy after an overdose of Special K, but doesn't remember where he left Emily after she also got high; Faith, Bosco, Sully, Ty, Doc and Carlos go out to search for Emily, and rush her to Mercy after she's found in critical condition; Faith and Fred blame each other for letting Emily go out with Eric.

As Faith waits for Emily to awaken from her coma, she blames everyone but her daughter for the overdose and reflects on the substance abuse problems in her family; after Cruz's sister is brought into the hospital with an overdose, Cruz gets Sully, Ty and Bosco to look the other way on any possession charges and sets off with Bosco to find the location of her supplier's meth lab, where they end up in an inferno when the dealer sets the house on fire; Kim is reluctant to give a statement in Carlos's case because she's feeling pressured to lie to save his career.

As she keeps vigil by Emily's bedside, Faith recalls her first days at the Police Academy and the beginning of her friendship with Bosco; the fire squad rescues Bosco, Maritza, and a very pregnant Linda Barnes from the inferno, but Lettie Cruz succumbs to her drug binge before they can reach her; Emily is released from the hospital and takes responsibility for her overdose; Bosco tracks down Gary Barnes with Linda's help; Maritza and Bosco's relationship goes to a new level when he attempts to comfort her on the lost of her sister; Kim finally testifies before the review board and stands up for Carlos.

Sully hits bottom when Ty washes his hands of the partnership after Sully's drinking goes completely out of control; a thief strikes fear in the hearts of the police when he phones in false ""officer-in-need-of-assistance"" calls to cover his fur store robberies; Faith and Maritza go at it after Maritza's lonesome cowboy tactics nearly get another cop killed, and Faith is forced to shoot a perp to save Maritza's life after she goes after the perp without backup; Doc has an unpleasant encounter with Joy's father; Faith is disgusted when she finds out about Bosco and Maritza, and Maritza confirms that she put Bosco in front of a lie about a dying declaration to obtain a conviction on a drug dealer; Ty overcompensates for Sully's inattention to the job by becoming a ""supercop"" with an eye to getting a gold shield.

Faith rebuffs Bosco's attempt to apologize for lying to her; the fire squad extricates a driver impaled after crashing into a store; after Doc makes an impassioned defense of Carlos before the review board, a re-energized Carlos goes back out on the street; Sully's job performance continues to decline as he neglects to keep an eye on a woman he was supposed to be guarding, and she snatches her critically ill baby from Mercy's E.R.; after they discover that the woman is mentally ill, Ty takes a multi-story tumble while trying to prevent her from jumping off a roof with the baby; Faith is stunned when an initially reluctant Emily is eager to continue visiting a drug counselor; Ty catches Sully drinking in the R.M.P. and seeks advice from a union rep; Carlos loses his job as part of the department's settlement with the West family.

In a last-ditch effort to save Sully's life, job, and pension by getting him dried out, Ty and Bosco kidnap him and bring him to a cabin deep in the woods where he hallucinates about the circumstances surrounding the deaths of Tatiana, Chevchenko and Ty's father, and his subsequent descent into alcoholism.