is an American police procedural television series created by Quinn Martin and Philip Saltzman for ABC and co-produced with Warner Bros. Television, with sponsorship from the Ford Motor Company, Alcoa and American Tobacco Company (Tareyton and Pall Mall brands) in the first season.

Starring Efrem Zimbalist Jr., Philip Abbott and William Reynolds, the series, consisting of nine seasons and 241 episodes, chronicles a group of FBI agents trying to defend the American government from unidentified threats.

Efrem Zimbalist Jr. played Inspector Lewis Erskine, a widower whose wife had been killed in an ambush meant for him.

Stephen Brooks played Inspector Erskine's assistant, Special Agent Jim Rhodes, for the first two seasons.

Lynn Loring played Inspector Erskine's daughter and Rhodes' love interest, Barbara, in the twelve episodes of the show's first season.

The most famous instance was in the April 21, 1968, episode, when Zimbalist asked for information about fugitive James Earl Ray, who was being hunted for the assassination of Martin Luther King Jr.

[3] The premiere episode of the first season, "The Monster," about a handsome serial killer who strangled women with their own hair, so shocked Tolson that he recommended the show be cancelled.