Follows the further adventures and misadventures of Hiccup Horrendous Haddock the Third as his Viking training continues and his father leads a stranger and the Hairy Hooligans to the Isle of Skullions in search of a pirate's treasure.

Hiccup Horrendous Haddock III's loyal dragon Toothless has been captured. The nanodragon is about to be gobbled and Sharkworms are on the loose. With the tribe of the Hairy Hooligans in disarray, it's up to Hiccup to prove himself a true Viking Hero.

To save his dragon from being banished, Hiccup must sneak into the public library and steal the Vikings' most sacred book.

Hiccup Horrendous Haddock III must go to great lengths to find a potato, the only thing that will cure his friend Fishlegs of the deadly disease Vorpentitis.

Hiccup, the reluctant Viking hero, has three months, five days, and six hours to discover America, return to Berk, save his father, battle Polarserpents, and win the annual Inter-Tribal Friendly Swimming Race.

In exile, and hunted by dragons and humans alike, can Hiccup the Viking find the dragon's jewel and save the world from destruction?

Stranded on the exceptionally dangerous, and possibly haunted, Beach of the Broken Heart, Hiccup must face UG the Uglithug and complete the impossible task — or die trying. Along the way, he'll have to battle Berserks, dodge Scarers, and save Fishlegs from being fed to the Beast, all while being hunted down by an old enemy with a dark secret about the mysterious Lost Throne. With Toothless by his side, and time to stage his rescue running out,...