In an attempt to capture Dagur the Deranged after his escape from prison, Hiccup and his fellow dragon riders go on unexpected adventures and discover other species of dragons.
As the danger increases and the battles intensify, Astrid prepares a fresh group of dragon riders to protect Berk, while Hiccup sets out to take on the villainous Ryker and the army of dragon hunters who were able to capture Stormfly.
Toothless and Hiccup are rescued by an unlikely savior after they are tricked into entering a trap. Fishlegs seizes the opportunity to showcase his leadership abilities when the situation escalates.
The Dragon Riders demonstrate their good intentions by rescuing Queen Mala's dragon, which was taken by Viggo. Hiccup embarks on a mission to seize the Dragon Eye from Viggo.
As he tries to control a volcano that threatens to destroy everything, the Dragon Riders discover Hunter's secret new activity and must do everything in their power to stop him.
Johann begins his journey with Hiccup in search of the precious stones, but Johann must discover the secret of the conspiracy being hatched against him and his friend.