While the rest of the Moomin family are in the deep slumber of their winter hibernation, Moomintroll finds himself awake and unable to get back to sleep. He discovers a world hitherto unknown to him, where the sun does not rise and the ground is covered with cold, white, wet powder. Moomintroll is lonely at first but soon meets Too-ticky, a wise spirit who sings mysterious songs, and his old friend Little My (who takes delight in sledging down the snowy hills on Moominmamma's silver tea tray).