In the novel, the protagonist Kip, a high school student, enters a competition to win an all-expense paid trip to the moon. Unfortunately, he comes in second and his prize is an old, decommissioned space suit. Though disappointed, Kip works at restoring the suit- he calls it Oscar-to working order. Needing money for college, Kip decides to sell Oscar but takes a good-bye night walk in the space suit, idly transmitting on Oscar's radio for fun. To his shock, he receives an answer from someone named "Peewee" and a space ship appears overhead, having homed in on his radio signal. A young girl in a space suit and a vaguely cat-like alien flee from the ship but are pursued by a hideous worm-faced alien who quickly captures both of them and Kip as well. Kip, still wearing Oscar, finds himself imprisoned on the ship and headed for outer space, along with Peewee the precocious preteen girl, and the gentle cat-like alien she calls the "Mother-thing".