Woolly, a mammoth, and Fang, a saber-toothed tiger, are born on the same day. Saber-toothed tigers hunt and kill mammoths, but mammoths are not easy prey. Food becomes scarce, and Woolly's tribe has to migrate. While leaving the glacier, the tribe is attacked by Fang's parents. At the end of the action-filled story, Fang and Woolly are left alone on the glacier. The author invites the reader to tell the rest of the story. Engaging illustrations support the text.