
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.

Danny and Baez join a narcotics task force to track a drug supplier; Baez comes into contact with drugs and gets an accidental overdose; Jamie and Eddie work to protect a rehabilitated sex offender; Frank forms an unlikely alliance with Mayor Dutton.

Jamie and Eddie ask Erin to drop old charges against a man who bravely rescued a woman from a local hostage situation; Danny and Baez work a case involving car thieves and discover the leader is a mobster they've dealt with before.

When a journalist disappears while working on an exposé about an innocent man serving time for murder, Danny and Baez hope that re-examining the original case will help them find her.

Anthony is shot while interviewing a witness; Erin enlists his archenemy, Danny, to investigate the case; Jamie and Eddie get in the middle of a standoff between a police lieutenant and a developmentally disabled man posing as an officer.