It's been a month since Dragons and Vikings were brought together, now the only thing left to do is train them.
Its close to winter in Berk, putting everyone on edge for food.
Hiccup, the chiefs son, also the one that brought dragons and Vikings together isn't worried about the snow at all.
He's usually the one to take advantage of the snowy weather, going dragon sledding with Astrid and the gang.
But when Hiccup, mysteriously falls ill with an unknown sickness, Stoik's worries for his survival in the cold grow.
In hopes to cure his only son Stoik sets out to sea to find the right medicine leaving Hiccup in the constant care of Gobber and Astrid.
When tragic strikes, and Hiccup is now left on his own, his chances of surviving become small.