The detectives investigate the brutal murder of a young woman. Their investigation leads to one main suspect – Derrick Cobb, the girl’s former stepfather. Simone worries that one of his close friends, Raymond diSalvo, has gotten involved in drug dealing at a dance club. Lesniak investigates con artist Mac McClellan.

A man goes on a shooting spree, killing a waitress, two cops and three other citizens before he was apprehended. Meanwhile, Lt. Fancy speaks on behalf of Reggie after Reggie squares off with Sgt. MacNamara.

Simone becomes attracted to an undercover cop, Diane Russell, as they work together to capture an arsonist. Sipowicz becomes personally involved in a case after a woman he convinced to testify in a case is murdered. Martinez and Lt. Fancy square off at the annual department boxing tournament.

Ronnie Drucker, a detective under investigation, is reassigned to the 15th squad and compromises Simone. A young girl, confused by drugs, is the only witness to a shooting in a laundromat.

Russell wakes up in Jimmy Leiry's bed and doesn't know what happened. There's been a strangling in a mainly Polish community. A man is found shot dead, in a quiet neighbourhood. Everybody knows him, but nobody saw anything.

Lt. Fancy falls fowl of an over zealous patrolman. Sipowicz is reminded of his son's death when he and Simone investigate a series of bar hold-ups. Martinez, Medavoy and Russell have to deal with a confidence trickster.

3 Latino men shoot another, who's walking with his girlfriend, in what looks to be a gang related feud. Martinez and Medavoy search for the killer of a man in a car repair shop. Russell and Kirkendall investigate the death of a baby, while in the care of a child-minder.

Danny wakes up in Diane's bed. Andy and Katie get Theo's test results. A former colleague of Bobby's reaches out to Diane from prison. The team investigate a series of cab-driver shootings.

Fancy bawls out Diane and Danny about being in a relationship. A man traveling on the subway is killed. Denby is implicated in the courier scam.

Danny is restored to full duty. Off. Szymanski's cousin is knocked down in the street and killed. Capt. Bass's wife is injured during a robbery at her store. Greg plays matchmaker.

A man caught carrying a cash register takes Andy and Danny to a body. Fancy is packing up to leave. His replacement alienates the squad before he's even left.