Jaime goes undercover with a deadly human trafficking ring. Danny and Baez investigate a homicide connected to Danny's old partner. Frank grapples with whether to publicly support Mayor Chase on a policy decision and Eddie is determined to teach a young shoplifter a lesson.

Danny and Baez join forces with Danny's old partner when a serial killer reappears. Eddie faces backlash when she tries to help a woman who accuses a sergeant of rape.

Frank grapples with the personal loss of his best friend and how best to help his daughter when she lands in jail. Jaime and his nephew race against the clock to reunite a trafficking victim with her sister. Danny and Erin clash when she goes behind his back.

Danny reunites with a troublesome teenager from a past case when the youth finds herself in danger. Frank faces a difficult personnel decision close to home. Jamie grows suspicious when Henry is asked to be interviewed for an investigative web series. Erin and Anthony investigate when Erin is the alleged target of a shooting.

Erin is designated to lead a federal investigation into corrupt horse racing. Jamie investigates a drug trafficking operation involving rival gangs. Danny and Baez look into a series of assaults in Little Vietnam with the help of a familiar face.

Danny and Baez investigate a homicide involving voodoo with the help of Baez's old partner. Eddie and a fellow officer team up with Captain McNichols when they suspect a prestigious school is employing discriminatory admission practices.

Jamie works to bust a group of scammers who use artificial intelligence to defraud the elderly. Danny and Baez investigate a series of mysterious deaths at a hospital. Anthony is determined to take down an attorney who exploits the law for his own financial gain. Frank disapproves when he learns Gormley is planning to face off against fellow officers in a friendly boxing match.

Danny and Baez are on edge when a serial killer, who once targeted Baez and her daughter, is released early from prison. Jamie and Anthony team up on an investigation involving one of Anthony's criminal informants, his ex-wife’s brother. Eddie clashes with Captain McNichols over a sergeant who keeps downgrading her cases. Frank is upset when Abigail goes behind his back regarding a professional favor for her husband.

Danny gets involved when Sean becomes the latest victim in a series of robberies on his college campus. Erin grows suspicious of an overworked attorney who she believes isn't acting in his client's best interest.

Danny and Gormley race to find a detective who is dangerously determined to uncover how a rapist he arrested is back on the streets.

The Reagans' professional lives converge when an allegation of jury tampering against Erin intertwines with Danny and Baez's homicide case and Eddie's bond to a child murder witness. Frank clashes with his friend and confidant Archbishop Kearns over the death penalty. When Jamie's car is stolen, he joins forces with his nephew to recover it.

Danny joins forces with British investigator Christopher Granger to pursue a deadly international fugitive. Erin faces pressure from her boss to secure an indictment against an officer.

Frank intervenes when tensions rise between Mayor Chase and the Fire Commissioner. Erin is blindsided when Henry agrees to testify for the defense in a case she is prosecuting. Danny and Baez investigate when human remains are discovered in a storage unit. Eddie and her partner navigate a complicated arrest when their criminal offender is scheduled to donate his kidney.

Danny and Baez scrutinize an art gallery suspected of selling counterfeit pieces after a detective investigating the establishment is murdered.

Danny and his nephew investigate the homicide of a delivery driver who may have been connected to an illegal narcotics ring. Eddie is determined to save the job of a probationary police officer who may be fired for responding to a crime. Frank faces a hard decision when he discovers Gormley is non-compliant with NYPD residency requirements. Erin clashes with her boss when a seemingly rehabilitated criminal from an old case becomes the subject of an armed robbery investigation.

Danny and Baez investigate when a star student is found dead in her dorm. Eddie and Badillo try to help a man whose apartment has been taken over by a squatter — who also happens to be Jamie's confidential informant. Frank suspects the Governor has an agenda when he comes to him with a proposal. Erin oversteps when she tries to play matchmaker for Anthony.

It's all hands on deck for the Reagan family, as they race to stop deadly mayhem in the city when the gangs of New York unite to demand amnesty and the release of their imprisoned members and those awaiting trial.