When the son of Frank's most outspoken critic is murdered, Frank and the boy's father must put aside their differences to seek justice.

When a key witness in Danny's case is killed just before testifying, Erin angers Danny by enlisting Anthony to help him find the killer. Robert Lewis tries to force Frank to publicly support the Attorney General's investigation of the use of excessive force. Eddie and Jamie get the call for an attempted suicide.

After Emily Harrison tells Danny and Baez she's concerned her abusive ex-boyfriend will repeat his behavior with his new girlfriend, she becomes the prime suspect when he's murdered. Eddie gets jealous when Jamie lets a young woman crash at his apartment. Frank must decide how to discipline a sergeant after he fails to intercede during an armed robbery while off duty.

Evidence against Danny surfaces when the attorney general's office reviews his shooting of a serial killer. Jamie and Eddie deal with a high-profile drunk driver. A slain cop's widow asks Frank for a favor.

When Danny intercepts a shipment of several million dollars that was heading to a drug cartel in Mexico, he becomes a target when they come back for revenge. Jamie works independently to track down a serial killer who preys on the elderly.

After a witness in a former case of Erin’s asks her for help shutting down a drug operation in his apartment building, she makes it her mission to make the building safe for his family. While investigating a teen’s suicide, Danny and Baez uncover information that suggests the death was a homicide. Frank looks into potential misconduct within the Mayor’s office.

Frank is left with minimal information to find a missing boy when a conflicted priest who could help won't break the seal of confession. Danny and Baez investigate the death of a prominent New York City socialite with a secret life. Jamie and Eddie attend a wedding together.

When Eddie and Jamie become overly involved in a complicated adoption case between the birth and adoptive parents, they ask Erin to help them settle the dispute without going to court.

When Danny accepts a side job as a bodyguard for a recently released ex-con who took the fall for someone else, he uses the opportunity to go after the real criminal. Gormley's wife, Sheila, asks Frank to give Gormley a bigger command position. Jamie and Eddie witness a lovers' quarrel between two cops that leads them to reflect on their own complicated relationship.

When diplomatic immunity complicates a child abuse case for Danny and Baez, Frank intervenes, despite not having jurisdiction on the case. A robbery occurs while Eddie and Jamie are on a double date with Eddie's boyfriend and his sister, and they are forced to step in.

While investigating the murder of a man who killed a mother and son years earlier while driving drunk, Danny and Baez are torn between doing their job and finding justice after discovering the connection between the suspect and the victim.

A woman who was held hostage resists pressing charges, but Danny and Baez want justice for her. A high-profile NYPD fundraiser uses a phony police vehicle to avoid traffic. Jamie has the opportunity to be a technical adviser on a TV show.

Intent on bringing justice to Lieutenant Gormley after he is beaten by a mob outside his home, Danny and Frank enlist the aid of Detective Abetemarco, who has a personal connection to the neighborhood where the attack occurred. Eddie and Jamie witness a dishonest arrest. Danny searches for a witness to testify against a dangerous gang leader.

An NYPD whistle-blower claims there's been abuse of power within the organization, so Frank must investigate whether this is true. Danny and Baez are suspicious of a car accident involving a pedestrian and think it may have been intentional.

While investigating the murder of a gang leader, Danny and Baez learn the accused shooter is an ex-con who is romantically linked to his parole officer, who might be assisting in a cover up. Concerned the murder might spark further violence, Frank steps in to mediate but must deal with a rival gang leader who killed a police chief two years ago.

Danny and Baez team up with two Russian operatives to search for a dangerous Russian man who entered the U.S. on a diplomatic visa. Frank gets involved in a sensitive case involving Archbishop Kearns.

Danny and Baez investigate the death of an elderly woman who was shot in her home by a stray bullet. Frank faces ridicule from his department when he disciplines a disrespectful cop. Erin steps in to help her detective find a legal solution to a case that’s personal to him.

Erin and Anthony try to prevent the deportation of a prominent community activist who isn't a citizen. Frank must decide if the NYPD will participate in the U.S. Marshals' high-profile raid of a local gang.

Jamie and Eddie suspect foul play when they respond to a distress call from a woman having an allergic reaction to her lifesaving medication, and learn that her husband is an EMT assigned to take her call, but didn't respond. Erin learns that a man she convicted years earlier might be innocent of the crime. Frank handles a PR crisis in his department when an exposé on Garrett Moore is published.

An ex-NYPD officer goes missing the day after she reveals to Danny her plans to make amends to the woman she and her partner wrongfully convicted years ago. Frank faces a dilemma when one of his peers refuses to retire.

When Linda's brother gets into trouble with the mob, he begs Danny to help him stay safe until it blows over. Frank faces a public relations nightmare when the lawyer of a wrongfully arrested man demands that NYPD records be made public.

Erin faces off against her ex-husband in court when he represents the person she is attempting to convict of murder. Frank is confronted by a mother who accuses the NYPD of being negligent in solving her son’s murder. Jamie rides with a new partner.