Rick is organizing a surf-ski competition to be held at the King Kamehameha Club (much to the disapproval of co-committee member Higgins) when a Kahuna appears and places a "curse" on the club and all who use it. Magnum and others are skeptical, but it seems there may be something in it when one of the competitors suddenly collapses and dies, fire breaks out in the kitchen, and Rick falls ill. Magnum investigates to try and find if there is a more logical explanation behind the events, but his inquiries aren't helped by a hounding news reporter, who sees the series of strange incidents as a chance for a big news story.

A bubbly young woman hires Magnum to find her father who, after being missing for over ten years, had sent her a postcard from Hawaii. But her father is involved in some rather shady business, and Magnum isn't the only one looking for him.