Buck, Wilma, and Twiki set off into deep space aboard the Searcher, a starship on a mission to find the lost tribes of Earth -- humans who fled to the stars after a nuclear holocaust that all but destroyed the planet. The Searcher encounters a severely-damaged spacecraft with one survivor, who tells them of a savage attack by a bird-man named Hawk. Searcher sets course for the planet where it is believed Hawk lives, and Buck soon becomes involved in a desperate battle of wits and piloting skills with Hawk. Hawk's mate, who was a passenger in Hawk's ship, is mortally wounded in the battle and Buck and Hawk form a shaky alliance to seek medical aid for her. Eventually, Hawk joins the crew of the Searcher, looking for others of his kind.