Utterly Dark has a special connection to the sea. But it is tested more than ever before, this autumn on the island of Summertide. Accompanying her uncle as he explores mysterious Summertide, Utterly is witness to strange happenings in the woods. Deep, old magic abounds, and threatens to steal those she loves most. Utterly must face truths about what lies beneath the land, and in her own past, if she is to save anyone. And she must make a sacrifice to the sea . . . An enchanting story of nature, magic and friendship, from the renowned author of Mortal Engines.