Washoe County Library System

Heart, a foundling who was discovered five years earlier wrapped in a unicorn-embroidered blanket, finds a pregnant white mare in the woods and struggles to keep her and her colt safe and well.

The old stories say that Castle Avamir is higher than the clouds, deep in a valley, under the stars, and over the moon. If Heart can't solve the riddle, she might never find a safe haven for her beloved unicorns.

When her beloved Moonsilver, the unicorn, is nearly killed by a hunter's arrow, Heart sneaks back into her village to get help from the healer, Ruth Oakes. Danger awaits and Heart must flee with Ruth's gift-a silver thread-to protect her and Moonsilver.