A dragon rebellion is coming filled with the meanest, nastiest dragons in the archipelago. Razor-wings, Tonguetwisters, and Vampire Ghouldeaths are attacking Vikings and seem to be seeking one soul in particular: Hiccup Horrendous Haddock the third! Only a king can save them ... and only a champion with all of the king's lost things can be king. In his adventures, Hiccup has collected quite a few "things" himself. But can a scrawny Viking save the entire archipelago from certain doom? To find out, Hiccup will have to outwit a witch, fight his arch-enemy, and beat back an army of bloodthirsty dragons with just one sword.