Danny accompanies a dangerous ex-mobster who is helping him find bodies on cold cases in exchange for leniency for his son on grand theft auto. Meanwhile, Jamie works undercover in a boiler room operation, looking for a secret about the Sanfino family.

When Erin's informant is murdered, she blames herself and works to help Danny discover who killed him.

Danny arrives at a college campus to find a murdered student, who was thought to be dealing drugs. Meanwhile, Jamie has a life crisis when he reconnects with a former law school classmate and Erin must learn to give Nicky some freedom.

Jamie must deal with the emotional consequences of his actions on the job. Meanwhile, Erin questions Mayor Poole on the witness stand.

Danny and Baez investigate a homicide in which Baez’s estranged brother, a former drug addict, is the lead suspect. Meanwhile, Frank learns one of his most highly decorated officers, a German Shepherd in the K9 unit, is being accused of police brutality, and Henry investigates the widow of a former NYPD pal who might have had a hand in her husband’s death.

Danny and Baez search for teenager who have been randomly punching unsuspecting people in the head, including a pregnant woman; Frank worries that promoting an officer will be viewed as favoritism.

Jamie gets Danny involved when he finds a homeless teen who claims his aunt was killed by her boyfriend. Meanwhile, Erin is angered when McCoy replaces her as the prosecutor on a case involving a corrections officer.

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 Anthony Abetemarco, who has a personal connection to the neighborhood where the attack occurred. Also, Eddie and Jamie witness a dishonest arrest, and Danny searches for a witness to testify against a dangerous gang leader

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

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. Also, Gormley's wife, Sheila, asks Frank to give Gormley a bigger command position, and Jamie and Eddie witness a lovers' quarrel between two cops that leads them to reflect on their own complicated relationship.

Erin’s trial against a notorious human trafficker is jeopardized when the presiding judge is mysteriously found dead. Danny and Baez are put on the case to investigate foul play. Meanwhile, Mayor Dutton opposes Frank’s public safety initiative, but City Council Speaker Regina Thomas devises a plan to help Frank bypass the mayor’s veto.

After a woman voices her outrage regarding the NYPD’s inability to find her son’s murderer, Danny reexamines the case, upsetting the original detective, Erin, and Anthony, who didn’t pursue the case due to lack of evidence. Also, Eddie is shot while on duty; Erin and her ex-husband, Jack, face off in court; and Frank contends with an angry police force when Mayor Dutton fails to defend them at a press conference.

Gormley looks to Danny and Baez for help tracking down a former NYPD detective he believes may be a threat to Frank's safety. Erin navigates office politics when she chooses to reopen a closed case. Jamie is transferred to a new precinct with a lot of problems. Frank and Baker team up to investigate a complaint about an SVU detective.

After an incident where Officer Witten’s backup physically could not keep up with a chase, Frank must decide whether to implement a more rigorous fitness test for the NYPD. Also, Danny is hesitant to pursue a cold case after learning who the original detective was; Anthony begs Erin to stall a murder trial so he can gather more evidence; and Eddie is vexed by Jamie’s disapproval of her joining a fraternal organization.

Erin disagrees with a psychiatric consultant's diagnosis of a nanny accused of abuse; Eddie confronts her boss; Frank is forced to make staffing changes he is skeptical about; a woman claims she heard someone plotting a murder.

Frank and Garrett devise a plan to convince Mayor Chase to work better with others in order to properly run the city, and Danny and Baez try to track down a perp who vandalized several NYPD vehicles with anti-cop graffiti and made threats against officers. Also, Erin is shaken after she's in a car accident, and Eddie and Jamie argue about whether they should keep a stray dog who leads them to a crime scene.

Baez confides in Danny and asks for his help in proving her innocence after she finds a corpse in her front yard. Also, Erin struggles to find a peaceful solution when she receives harsh case notes from her boss, Jamie and Eddie butt heads over the handling of a young cop’s punishment, and Frank makes his whole team attend therapy after Gormley exhibits troubling behavior.