A woman hires Magnum to protect "Norman", who is facing kidnap unless she pays a ransom, but the case has some unexpected turns when Magnum finds that her uncle is an old Vietnam comrade who is against him being hired, and that Norman is none other than a prized racehorse.

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, but soon finds himself involved in a real mystery.