The Angry Birds embark on a new adventure while King Mudbeard plots revenge against them and a mysterious purple bird threatens them all with her own plans for conquest.

Hiccup fulfills his dreams of creating a dragon utopia and rules it alongside Astrid. When the sudden appearance of female Light Fury coincides with the darkest threat their village has ever faced, Hiccup and Toothless must leave the only home they’ve known and journey to find the mythical Hidden World before a hired tyrant named Grimmel finds it first. As their true destines are revealed, dragon and rider will fight together—to the very ends of the Earth—to protect everything they’ve grown to treasure.