
Detective Steve McGarrett (Jack Lord) heads up Hawaii Five-O, a special division of the state police tasked with bringing down organized crime on the islands. The Five-O team works with local police from time to time on individual cases, and McGarrett's nemesis is crime kingpin Wo Fat. The show, which ran for 12 seasons during its original run, is famous for its catchphrase "Book 'em, Danno," said by McGarrett at the end of most episodes. The show's theme song, composed by Morton Stevens, became popular during the show's original run.

McGarrett takes his first undercover assignment when he poses as a merchant seaman to probe the murder of a labor-union reformer.

McGarrett travels to Los Angeles to investigate a physician who is victimizing his sister and her child.

A rising young politician (David Birney) is the victim of a blackmail scheme designed to squelch a congressional probe.

Despite public sentiment and a lack of damaging evidence, McGarrett takes Dr. Fremont (Joanne Linville) to court.