Miriam A. Hyman

Danny and Baez investigate the murder of a single mother whose ex-husband has a history of violence. Also, Frank deals with the fallout when Mayor Dutton (Lorraine Bracco) eliminates solitary confinement in prisons, and Jamie's efforts to save a young woman who overdosed on drugs has unexpected consequences.

When Danny and his family are threatened by Thomas Wilder (Louis Cancelmi), a serial killer Danny has been unable to apprehend, Linda's concern intensifies over her husband's job as well as the state of their marriage. Also, Jamie challenges his superior officer, Sgt. William Mulvey (A.J. Buckley), during a hostage situation.

As Frank contends with a whistleblower within the NYPD who claims to have evidence of abuse of power in the organization, Danny and Baez investigate the case of a woman who was struck by a car under suspicious circumstances.

After Reggie Wilson (Cyrus Farmer), 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. Also, while investigating a teen's suicide, Danny and Baez uncover information that suggests the death was a homicide, and Frank looks into potential misconduct in the Mayor's office.

Danny investigates the circumstances of an ex-NYPD officer who goes missing the day after she revealed to him that she had planned to make amends to the woman she and her partner wrongfully convicted years ago. Also, Frank faces a dilemma when one of his peers, Chief Taylor Daniels (Isaiah Washington), refuses to retire, even though he’s hit the mandatory age limit.