Hiccup is a clumsy young Viking who dreams of following in his father's footsteps and becoming a fierce dragon slayer. When he miraculously manages to down and injure the most dangerous dragon of all, Hiccup finally has his chance to prove himself with his first kill. Taking pity on the dragon though, he ends up befriending the creature, and when danger of a different kind threatens to eradicate his entire village, Hiccup and his new friend must go into battle.