- Directors: Chris Sanders, Dean DeBlois
- Producers: Bonnie Arnold, Michael Connolly, Tim Johnson
- Writers: Dean DeBlois, Chris Sanders, Story, Cressida Cowell
- Genres: Animation
- Actors: Jay Baruchel, America Ferrera, Jonah Hill, Gerard Butler, Christopher Mintz Plasse, Craig Ferguson
The film is set in a mythical world of vikings and dragons. The story centers around a viking teenager named Hiccup (Jay Baruchel), who lives on the island of Berk, where fighting dragons is a way of life. The teenâ€™s smarts and offbeat sense of humor is disliked by his tribe and its chief, Hiccupâ€™s father. However, when Hiccup is included in Dragon Training with the other viking teens, he sees his chance to prove he has what it takes to be a fighter. After he entangles a dragon with a bolas-shooting cannon, Hiccup releases and ends up befriending the dragon. This relationship flips his world upside down as he strives to convince his tribe that they do not need to be dragon-slayers. In the novel, the dragon which is named Toothless is incredibly small for a dragon. In the film, Toothless is a Night Fury, the rarest of all dragons, and is large enough to serve as a flying mount for Hiccup and Astrid.
In initial development, the plot followed the original novel closely but was then altered. About halfway through production, Chris Sanders and Dean DeBlois took over as co-directors. The original plot was “heavily loyal to the book” but was regarded as geared to a too-young demographic and too “sweet” and “whimsical”, according to Baruchel.