The story begins when Hiccup, his friend Fishlegs, and his cranky dragon Toothless get separated from their class during Boarding-an-Enemy-Ship practice. They accidentally board a prowling Roman galley intent on provoking war. When they rescue a tiny nanodragon, they uncover a plot to steal every dragon on the Isle of Berk!

This is just the start to an epic adventure that will have kids laughing from start to finish, and shines with Cressida Cowell's trademark blend of action, humor, heart, and engaging illustrations.