As evidence for the defense at his ongoing trial, the Doctor presents an adventure from his future when he is travelling with a computer programmer named Mel. Answering a mysterious distress call from the space liner Hyperion III, they find that the passengers aboard include unscrupulous scientists, secret agents, saboteurs, thieves and a murderer. And lurking in the shadows are the Vervoids, the product of sinister botanical experiments, who will stop at nothing to destroy all non-plant life.

A private investigator who works when he wants, lives in a beachfront estate in Hawaii, drives a posh Ferrari, runs up an unlimited tab at a swank bar, and charms attractive women in peril - that's the lifestyle of Thomas Magnum, aka Magnum, P.I.