It's the Christmas season, and against his better judgment, Magnum agrees to being hired by five young schoolgirls to find their teacher, who has seemingly gone missing after falling in love. While he's working on the case, Magnum manages to convince Higgins to let the young girls stay on the Masters estate, but he's unaware that he's being deceived in a scam over a valuable painting recently purchased by Robin Masters.

Higgins volunteers Magnum's services to guard a wealthy socialite's quarantined dog after the attempted dognapping of the canine. Sir Algernon Farnsworth soon finds himself to be the most wanted dog in Hawaii when his former owner, aging gangster Victor DiGiorgio, needs to get him back.

T.C. makes a late-night flight to land on a tanker, but on the journey back he is cornered and arrested by the Coast Guard for transporting drugs. Magnum and Rick are certain of their friend's innocence, but are shocked when he intends to accept the charges and refuses their help.

Magnum has been hired by a woman to act out some of her rich, bored sister's fantasy dramas, concocted from 1930s Dashiell Hammett films. Although growing to enjoy the world of fantasy, Magnum has a hard time keeping up with the eccentric woman, and when he finds out that her husband is a wealthy, infamously jealous and bad-tempered business man, he decides to cut his losses and end the arrangement.

Part 1 of 2. A tragic event which he believed had been successfully relegated to the far corners of his mind, resurfaces and explodes with jolting clarity for Magnum, when he briefly sees a girl he is convinced is his wife, reported dead in the ruins of Saigon.

Mad Buck Gibson, an old friend of Robin Masters and a legend in his own time for his earthy novels and macho existence, arrives in Hawaii and it becomes Magnum's lot to protect the hell-raiser from himself.

An eccentric, reclusive inventor, a beautiful author and a distraught senator's wife form the strange triangle surrounding Magnum as he tries to unravel a situation that could lead to sudden death.

A private investigator with amnesia is really in trouble, as Magnum discovers after his near fatal accident with the Ferrari leaves him in that condition.

When Robin Master's latest book is made into a motion picture, the author donates the use of Robin's Nest as a location and Magnum is quickly enmeshed in the temperaments and politics of the film world.