Buck is haunted by the appearance of a young woman who bears a striking resemblance to Jennifer, a woman who Buck left behind when he was propelled into the 25th Century. He follows her, finds out her name is Leila Markeson, and soon discovers that she was made to look like Jennifer in order to lure Buck into a trap set by an alien who wants Buck to stop a space freighter from delivering weapons to a planet his people hope to conquer. Buck gets Wilma to detonate a warhead to deceive the aliens into thinking the shipment is destroyed. Buck defeats the enemy, but loses Leila, and his lost love again, as she tearfully dies in his arms.

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.

Buck, Wilma, and Hawk explore a strange planet and come across the wreckage of a spacecraft and its lone survivor. He is taken back to the Searcher by Wilma, while Buck and Hawk continue to explore. After some unexplained happenings on the planet, they return to the Searcher, where they find that everyone has undergone personality changes -- becoming the opposite of their real selves. Buck soon learns that he can not even trust Wilma and Hawk to help him solve the mystery of what has happened.

Buck and Hawk are sent to pick up the survivors of a planetary disaster and transport them to a new home. Before departing, Buck rescues a young woman from a group of Dorian thugs. Later, while enroute to the planet, the Searcher is attacked by a Dorian craft, which demands that the woman be returned for the murder of a warlord's son. As the Dorians persist and subject the Searcher to a severe pounding, the refugees begin to rebel, insisting that the woman be turned over. Eventually, Buck discovers that truth about the woman and the startling reason why the Dorians always wear what at first appear to be merely ceremonial face masks.