Jaime goes undercover with a deadly human trafficking ring. Danny and Baez investigate a homicide connected to Darryl Reid, Danny's old partner. Also, 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, Jackie Curatola, when a serial killer reappears. Also, 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 Tess Ross, the daughter of his best friend, when she lands in jail. Also, Jaime and his nephew, Joe Hill, race against the clock to reunite a trafficking victim with her sister; and Danny and Erin clash when she goes behind Danny's back to use his criminal informant in an investigation.
Danny reunites with a troublesome teenager from a past case when the youth finds herself in danger. Also, Frank faces a difficult personnel decision close to home; Jamie grows suspicious when Henry is asked to be interviewed for an investigative web series; and 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. Also, Jamie investigates a drug trafficking operation involving rival gangs and 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. Also, 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. Also, 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; and Frank disapproves when he learns Gormley is planning to face off against fellow officers in a "smoker" boxing match.
Danny and Baez are on edge when Sam Evans, a serial killer who once targeted Baez and her daughter, is released early from prison. Also, 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; and 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 Sean's college campus. Also, 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 Gus Vanderlip, a committed 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; and when Jamie's car is stolen, he joins forces with his nephew, Joe Hill, to recover it.
Danny joins forces with British investigator Christopher Granger to pursue a deadly international fugitive, and Erin faces pressure from her boss, D.A. Crawford, to secure an indictment against an officer.
Frank intervenes when tensions rise between Mayor Chase and the fire commissioner of New York City. Also, 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; and Eddie and her partner Badillo navigate a complicated arrest when their criminal offender is scheduled to donate his kidney.
Danny and his nephew Joe Hill investigate the homicide of a delivery driver who may have been connected to an illegal narcotics ring in the city. Also, 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; and Erin clashes with her boss, D.A. Crawford, when a seemingly rehabilitated criminal from an old case becomes the subject of an armed robbery investigation.