
Tom Selleck stars as Frank Reagan, the New York Police Commissioner, and patriarch of the Reagan clan, a multigenerational family of cops. Frank's oldest son is Danny, a seasoned detective and Iraqi War veteran who occasionally uses dubious tactics to solve cases. Daughter Erin, the lone female, is an assistant district attorney. Fresh out of Harvard Law, Jamie is the youngest member and "golden boy" of the family. Jamie gave up a lucrative future in law to continue the family's tradition in police work, and is asked to participate in a secretive investigation that even his father does not know about.

An investigation becomes personal for Danny when a serial killer attaches a message for him on his latest victim.

When a witness in a murder trial flees out of fear of retaliation, Erin and Anthony must find him and convince him to testify; Garrett encourages Frank to attend the Police union party; Danny and Baez investigate a robbery at a convenience store.

Frank, the mayor, Erin and the DA's office deal with public outrage when a grand jury fails to indict an NYPD officer for the controversial shooting of a teen, which was caught on video.

Robert Lewis obtains new evidence against Danny in the shooting case of Thomas Wilder; Jamie and Eddie respond to a drunken driving accident involving a public figure; a slain police officer's wife asks Frank to keep her son out of the police force.