When his friend winds up dead, Magnum must find his killers and uncover a smuggling ring that leads him to people from his past during the Vietnam War.
Guest stars: Michael V. Gazzo and Kathleen Nolan A Supreme Court nominee hires Magnum to locate his ex-prostitute wife who has been missing since the Pearl Harbor Attacks forty years earlier.
With just a ten year old postcard as a clue, Magnum is hired by a Kansan woman, Cindy Lewellyn (Anne Bloom), to find her missing father Floyd (Noah Beery) who's a small-time con man on the run.
Because of a threat to his life, Robin Masters (voiced by Orson Welles) hires Joy "Digger" Doyle (Erin Gray) to check the security at the estate.
After her archaeologist father's boat is found deserted at sea in the Nihoa Channel, a marine biology student hires Magnum to find out what happened to him.
A year after escaping from Moscow in a MiG 23 fighter jet, a Soviet defector hires Magnum to help his girlfriend defect from an Olympic track team visiting Hawaii.
[1] Magnum, T.C., and an ex-army buddy named Nuzo (James Whitmore Jr.) try to track down Ivan (Bo Svenson), a Soviet KGB officer who held them captive during the Vietnam War.
Magnum is assisted by the Simon brothers (Gerald McRaney and Jameson Parker) in finding a stolen Hawaiian artifact that's supposedly cursed.
Magnum investigates the crash of a small plane in the Estate's tidal pool and discovers it was not accidental and that the pilot Sam Houston Hunter (William Lucking), he vaguely recalls, helped save him in the Vietnam War.
A young woman named Diane Dupres (Sharon Stone) claims she is being stalked by her twin sister, Deirdre, and hires Magnum to investigate.
Another of Higgins' half-brothers arrives (John Hillerman in a dual role), this one the last in the royal line of Costa Del Rosa and who ends up a suspect in a plot to assassinate the country's president at a chess tournament.
While the others are away, Magnum begins the hated task of filling out his tax forms for an audit but is interrupted by a phone call from a serial killer with a nursery rhyme for him.
Jessica Fletcher (Angela Lansbury), on vacation in Hawaii, offers to help Magnum, who has been accused of killing a hitman with an unknown target, and continues in his corner when another murder occurs.
During a hike in the mountains to clear his head, Magnum becomes trapped under the wreckage of an old fighter plane and must stay alive, while also thinking about a case he was recently fired from and reminiscing about his life in general.
named Michael Doheny (Frank Sinatra, in his last credited screen acting performance) to find the killers in an unsolved Bronx homicide, who are now living in Honolulu.
Still healing from his near-death ordeal and experiencing Mac's ghost, Magnum is surprised when Higgins hands over his estate duties to be able to take some time off.