How to cheat a dragon's curse

Hiccup Horrendous Haddock the Third is a smallish Viking with a longish name. Hiccup's father is chief of the Hairy Hooligan tribe which means Hiccup is the Hope and the Heir to the Hairy Hooligan throne - but most of the time Hiccup feels like a very ordinary boy, finding it hard to be a Hero. Hiccup's best friend Fishlegs thinks he has a nasty cold, but Old Wrinkly has diagnosed . . . VORPENTITIS, caused by the sting of a Venomous Vorpent, which is pretty much ALWAYS FATAL! The only antidote is the Vegetable-that-No-one-Dares-Name - the POTATO. But the only way for Hiccup to find the cure is to face Norbert the Nutjob and the terrifying Sea Dragon, the DOOMFANG. Can Hiccup survive the quest to save his best friend - and discover how to cheat a dragon's curse?