Danny unravels a judge's complicity when he favors a sex trafficker and FBI informant against the mob. Frank gets closure for a case from his policing days of a boy who had disappeared. The boy's remains and a confession achieve that.
When the son of a Russian gangster is killed at his own engagement party, Danny delves into the world of the Russian mob and the family politics that exist. Meanwhile, Erin is thrown into a high-profile corruption case.
An undercover cop, who had infiltrated a terrorist cell, is shot. A girl, with acute anxiety and living alone, frequently complains that her house furniture has been disturbed. Danny solves the shooting and Jamie apprehends the intruder.
When a young girl is tied up, gagged and held for ransom, Danny and Jackie place her drug-addicted boyfriend at the top of their suspect list. Meanwhile, Erin and her boss, Charles Rossellini, take their flirtatious banter a step further.
When an assassination attempt is made on Frank's life, Danny goes on a hunt to track down the shooter and find out if the attack was random or by someone with a vendetta against the Commissioner.
Nicky, Erin's daughter, writes a school paper on policing, and is upset when she sees a real dead body. Danny solves that murder. Jamie apprehends an art student who sprays art work on walls and shop shutters. He is let go with a warning.
A much decorated, awkward and homeless Marine gets beaten to death by 3 cavalier, rich guys in a back alley. Danny, an ex-Marine, is distraught by the outrageous act. After a difficult investigation, he succeeds in solving the case.
Danny chances upon a fatal shooting outside a store. His investigation reveals that the shooter is a Peruvian mob boss. The police arrest this killer but Danny's wife is kidnapped, to pressure him not to testify. His wife is then rescued.
When Linda's runway model niece and another model collapse at a fashion show, Danny and Jackie immerse themselves in the cut-throat world of fashion to find the culprit who poisoned them.
When a tourist from Iowa who is visiting the city with his wife gets mugged and shot, the press soon puts the pressure on the police to solve the case fearing for New York's reputation with tourists.
An elderly couple known to the Reagans is murdered in their house in the neighborhood, Jamie's service weapon gets stolen from his locker and Frank fights the mayor about the police budget.
Jamie shares his suspicions with his family about Joe's killing and the now infamous Blue Templar. A private investigation leads them to the police officers who are the ring leaders of this secret group. Joe's death gets a fitting closure.
A married, family man and supporter of the new Mayor, involved with a Croatian girl, is shot dead. The Mayor is averse to bad press. Frank stays on as Commissioner. Plain-clothed Jamie unknowingly helps a mob member who had over-dosed.
When Danny shoots a cop who failed to identify himself, he is put on modified assignment and must face an Internal Affairs investigation, which delves into his personal state of mind that day.
When a bank robbery turns into a hostage situation, Frank realizes that the perp is a former cop and old friend who has resorted to crime because of his daughter's desperate illness.
Erin reopens an 18-year-old rape case in which Frank was the arresting officer. Meanwhile, Danny and Jackie investigate the murder of three teenagers in a park who seemed to have been killed for no reason.
Danny tries to juggle investigating a case with trying to have a romantic weekend with Linda. Meanwhile, Jamie goes deep undercover into a crime family.
Frank deals with a political crisis after Jamie and Renzulli enter a religious center in response to a 911 call and are injured by the church's security team who prohibits them from entering.
An escort is murdered in a hotel room. Sensing a pattern, Jackie poses as a decoy escort. Frank has budget constraints but resisting unions. Henry declines a consultant's role in a private agency looking to profit from outsourcing in NYPD.
A girl falls from her apartment window and dies. Danny investigates. Henry has a heart attack and spends Thanksgiving in the hospital. Tony gets cash to square off his gambling debt, with a warning from the Commissioner.
Jamie goes undercover in a boiler room operation, selling stocks on cold calls, to get their client list with criminal links. Danny drives around a convicted mobster who reveals murdered bodies, in a deal to help his carjacking son.