Peer and Hilde are thirsty for adventure. When a Viking longship arrives in their village, they set sail, eager to explore the world. The Water Snake is heading for Vinland, a place far across the sea inhabited by a civilization of people and new mysterious creatures, some good and some perilous.

But dangers untold lie closer than Peer and Hilde could have imagined. The ship's captain and his sword-wielding son are not what they seem, and Peer is forced to flee alone into the wild unknown. When dark forces and kindly creatures both vie for his life, Peer must rely on the help of strangers and befriends the natives of Vinland. At the end of it all, where will his loyalty lie?

In this final novel in the Troll trilogy, Katherine Langrish crafts a rich story where Viking legend is intertwined with Native American life and lore based on the Mi'kmaq people. As mysteries abound, Peer and Hilde struggle to survive in a new realm of wonder and menace.