Speed and self-confidence, that's Astrid's motto. Nicknamed "the little thunderbolt," she loves to spend her days racing down the hillside on her skis or sled, singing merrily as she goes, and drinking hot chocolate made from real chocolate bars with her grumpy best friend and godfather, Gunnvald. She just wishes there were other children to share in her hair-raising adventures. But her world is about to be turned upside down, first by the arrival of a family with children to her village, and then by a mysterious woman whom everyone but Astrid seems to know. Gunnvald has been keeping a big secret from her --one that will test their friendship. Astrid isn't happy about all the changes in Glimmerdal. Luckily, she has a plan to set things right.