When the government observation station is left unmanned, Hal and his cat Susie are summoned to help the little aliens who have landed nearby escape from some new arrivals from outer space — the evil, blobbish Ness. Hal's help is needed because the aliens can't plan without the leadership of their head Think-Think, whom the Ness are holding in chains. Sure enough he calls on the Gotchas — those rock-like animals who can trip an unwary intruder — and comes up with a slick solution. Gilbert visualizes these manic creatures with enthusiasm and they are a nice break from the humdrum reality that beginners like Hal are usually stuck with.