Ellsworth, an only kitten, dreams that a purple spaceship lands outside and its green Cat-Martian passengers peek in his bedroom window. That day when his mother goes shopping, the dream returns and Ellsworth wakes to find a headset, which puts him in touch with green Cat-Martian Margaret. She gives him a little one-cat spaceship but warns him never to take it beyond his yard. Well of course Ellsworth does, eventually heading straight for the sun and finding himself lost in space. Fortunately he's wearing his headset and an SOS to Margaret brings the purple ship to his rescue with a tow home. The story is elementary and the pictures--sometimes one, sometimes four to a page--are flat, trim, and cookie-cutter simple; yet together they have a straight-faced believe-it-or-not-ability for curious, well-wishing onlookers.