Feeling betrayed, Doc angrily confronts his former friend, Jerry Mankowitz, an attorney's investigator who tricked him into confiding vital information about a pending malpractice suit.

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

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.

Maritza calls on her own experience to persuade a rape victim to identify his attacker and sign a complaint after she collars the perp and gets a confession; Ty's prison visit to his father's killer has devastating consequences for both of them; Faith frantically searches for her son when Fred's girlfriend reports that he's missing; the former partners come to blows after Ty accuses Sully of being part of the cover up in the death of Ty's father; both Ty and Sasha deny telling I.A.B. about the knife when Maritza questions them; Sasha uncovers further details about the conspiracy to murder Ty's father and the ensuing cover up.

The Boscorelli family suffers a tragic loss at the hands of Donald Mann, who blames Bosco, Faith and Maritza for the death of his son in a high-speed chase; the Yokas family heads off in different directions; the Martin family splits apart into separate jail cells for the parents, and a return home for Rebecca to the mother from whom she was stolen as an infant; the paramedic family at the 55 gets a new member, Grace Foster, which makes no one involved very happy.

It is September 21, 2001, and the squads continue to battle through their emotions and their misgivings about their hero status, while working double shifts and spending every free moment at "the pile" searching for the missing. Kim returns to work and teams up with Doc, which allows an emotionally frayed Alex to return to paramedic duty; an exhausted Sully attempts to co-exist with his prospective in-laws while he waits for an opportunity to marry Tatiana.

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.

Faith negotiates the end of a live on TV hostage situation. The leader of a vampire cult holds Emily hostage until Bosco saves the day. Cruz attempts to negotiate a deal with a gangbanger to end the war on the 55th Precinct, but instead, he organizes his troops to attack.

Internal Affairs drops the bomb on the envelope-pushing Detective Cruz as she is taken away and struggles to survive in jail, while Captain Finney drills Detective Yokas for information that will nail Cruz - but the torn cop secretly knows that she pulled the trigger on a career criminal that frames the case against Cruz. Officer Sullivan reveals more about his running feud against Finney and his rookie son. Carlos and Levine keep getting called to help a suicidal woman. Bosco's condition changes.

During the investigation of the gang shootout, the police officers are questioned and presented with evidence that suggests that Ross was killed by friendly fire; Carlos learns that Vangie is dead and that he is the father of the baby her sister leaves at the firehouse; on the first anniversary of Bobby's death, Kim quarrels with Jimmy over her visitation with Joey and confronts a female gang during a call; and Doc is visited by the father of a former patient whose debilitating injury may have been caused by Doc's error during treatment.

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

Carlos has a life-changing experience in the hospital after he falls down the fire pole. Tatiana leaves her mother-in-law alone in the house for a moment, with disastrous results.

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.

Bobby's attempt to keep Paulie away from drugs ends tragically.

Kim and Jimmy are having a custody battle over Joey. Boscoe and Faith are on a call of a possible terrorist threat, that ends up being an explosive event. Alex risks herself to save a little girl and is punished by Doc for it.

After a despondent woman steps off an eight-story apartment building, the squad finds themselves in a race to transport both the woman's heart and a dying girl to a local hospital in time to save the youngster's life. The suicide hits home for Faith as she comes to grips with her own ongoing medical problems, while Doc expresses concern over the emotional effects this case will have on Kim, despite her constant reassurance that her accident was not an attempt to kill herself.

Kim is invited to a party by Noble. Noble is arrested through an undercover operation. He becomes an informant and helps Cruz and Bosco bust a Meth ring. Faith officially requests a new partner. Emily and Faith face off about Eric.

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.

Faith investigates Bosco further, Sasha and Ty make up, Cruz goes for some spiritual healing, Carlos meets Holly's parents.

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.

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.

No one can find Bosco after a sexual assault suspect is found dead. While Bosco spends time with family, Yokas, Ty and Sully try to clear him as a murder suspect. Still locked in a custody battle over Joey, Jimmy and Kim meet with a court-appointed evaluator and plead their cases. Alex tries to stay busy to avoid dealing with her feelings about her father's death.

The three squads are stationed at the Waldorf-Astoria Hotel to provide protection during a Clinton-Giuliani Senate race debate. The cops are assigned to the kitchen and discuss politics and the death penalty while Sully tries to get a reluctant head chef to feed them. The paramedics are parked in the hotel's garage where they talk about their worst cases, religion, relationships, and how life doesn't turn out as planned. Kim and Jimmy have it out again over his irresponsibility after her paycheck is garnished to cover one of his bad debts, and Jimmy resolves to clean up his act.

Jimmy gets a promotion to a rescue squad in Brooklyn; despite their new captain's assurances, Doc suspects that he intends to close down the house; Sasha insists upon pursuing an investigation into the beating death of a hit-and-run driver after Maritza uses the confession of an innocent man as her stepping stone to an Anti-Crime reassignment; after Jimmy is trapped in a warehouse fire, Kim reassesses their plans for a future together; Rose's serves a customer at the bar who shares a past with Bosco.

The two rookies, Carlos and Davis, experience disillusionment with their new jobs, and their training officers. Bosco struggles with Homophobia and gets himself involved in tit for tat games with Doherty.

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.

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.

Dealing with the aftermath of gang warfare, Doc and Carlos disagree over reaching out to prevent an eleven year old boy from following his brother into a gang; Bosco's decision to turn the tables on two men who try to rob him when he's off-duty could cost him his badge when the two men turn up at the precinct to report the crime; as he continues his losing streak, Jimmy gets deeper and deeper into his bookie, which puts Joey in danger; Kim begins to worry about how much time she spends with Joey after he gets into trouble at school.

Sasha, Bosco, Sully and Ty get on the case of a malicious rapper. Ty considers returning to law school with the help of Sully. Jimmy struggles with his new position and his relationship with his co-workers when he makes a big mistake during a fire drill. Faith gets a physical therapist.

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.

Bosco is caught on a security camera having sex in his squad car with the daughter of his Precinct Captain. Meanwhile Doc drags Carlos around the city on a personal mission to find the owner of a watch, found in the ambulance.

Doc and Carlos attend a stress debriefing; Carlos meets up with Bosco when he's ordered to attend sensitivity training.

Bosco gets a temporary assignment working with a tough female sergeant; Fred is strangely calm in the face of the prospect of a triple bypass; Doc hears shocking news from Philadelphia; Sully learns more about Tatiana's past; Davis is forced to deal with his newfound fame.

Joey starts a fire while on a field trip with his class, causing Kim and Jimmy to reevaluate their parenting styles and inspiring Kim to try to rebuild her family, starting with a reconciliation with Jimmy. But Jimmy's relationship with Brooke is not nearly as wobbly as Kim would like to think, and Kim ends up jumping into bed with a stranger and then commiserating with her mother over her problems with men, ending in a confrontation with Brooke that forces Kim to rethink what's best for Joey in the matter.

Bobby comes to the aid of his old friend Paulie after Paulie's sister begs Bobby to help her brother with his drug addiction, but becomes enraged when Paulie breaks into Bobby's mother's house and robs her to support his habit.

Mercy's new E.R. attending gives the cops and paramedics a hard time while ignoring Carlos's attempts to hit on her; Doc is saddened to hear that Jerry has decided to take a disability retirement; Jimmy is upset when Joey goes to Bobby first after he becomes ill as a result of Jimmy's letting him overindulge in sweets; Jimmy and Bobby take out their conflict over Kim and Joey in a game of one-on-one; Sully and Ty arrest a purse snatcher who will do anything to stay in jail once he discovers that his victim's son is a mobster; Faith hands out street justice to a gangbanger responsible for the deaths of two little boys.

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.

Doc is thrilled when Sarah accepts his proposal, but is stunned when she informs him that she's accepting a job offer in Philadelphia and wants him to relocate.

Doc, Carlos, and Ty each feel guilty about the mistakes they made during Jerry's shooting; Jimmy gives Kim a bulletproof vest; the squads rescue a man dangling from the side of a skyscraper after an explosion; Fred wants Faith to quit her job; initially reluctant to discuss the circumstances surrounding Ty's father's death when Ty asks, Sully finally relents; Carlos and Ty commiserate about their partners; Sully's contacts on the street pinpoint an abandoned building as the location of Jerry's shooter, and Bosco takes the shooter down -- out a second floor window.

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.

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.

Faith's excitement over having her husband to herself for the weekend is dashed when Fred decides to spend the time trying to win a truck; angry, Faith organizes a drunken girls night out, meets a handsome photographer, and ponders an affair and what might have been; Fred outwits his opponents and wins the truck.

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.

A disturbing visit from his former high school girlfriend forces Doc to confront a horrible act he has hidden for years; Carlos struggles to pass a medical school qualification exam.

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.

As he comes around a corner in pursuit of a gunman, Davis shoots a man who is pointing a gun at Sully, unaware that the man is innocently returning the service revolver which Sully dropped when he fell. Davis's guilt leads him to doubt whether he should remain on the force, until Sully straightens him out. The tension between Bosco and Faith continues to escalate. Both Bobby and Jimmy introduce their new girlfriends to Kim, who isn't thrilled with the potential competition.

When a doctor comes to New York to search for the missing daughter of her drug-addicted sister, Faith and Bosco focus their attention on the child's stepfather, a New Jersey cop, after they discover that the girl was taken by a man in uniform; Tatiana returns home; Jimmy spends some quality time with Joey. The crossover starts on ER S08E19 Brothers and Sisters

Finney gets a frantic phone call from Ben, a child he had helped in a previous case, which said that Ben's father was hurting Ben's mother and coming after Ben. Ben's father takes him to an abandoned warehouse, where the police soon follow.

Yokas clashes with her mother over her recovery; Maritza is back on the job, but unhappy that she's back in the bag and handing out parking tickets; Ty and Sully discover a truck carrying sick illegal aliens and end up scouring the city to track down one of them who escapes after it's determined that the aliens have a highly contagious and potentially fatal disease.

Even though his co-workers want to nominate him for the "Paramedic of the Year" award, a pensive Doc is disheartened as he considers his unfulfilled life. He later teams with Kim as they try to save a heart-attack victim while fending off a woman wielding a meat cleaver. In addition, Doc tries to minister to a chronic old drunk and a teenaged girl who attempts suicide in her bathtub. Meanwhile, Faith secretly undergoes a procedure to determine if the lump in her breast is cancerous, leaving an unsuspecting Bosco assigned to a nervous rookie cop; Kim reluctantly consults a lawyer about Jimmy's intention to claim custody of Joey.

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.