According to The Hollywood Reporter, the sequel will move beyond the small, North Sea island that was the setting of the original film as it traces the further adventures of Hiccup as he grows toward becoming the leader of his Viking clan.
Dean DeBlois revealed he is currently working on the second draft of the screenplay, which he expects will be at least the second film in a trilogy.
"I turned in the script before the holidays, and got some notes back and I'm working on a second draft," Dean DeBlois said. "It's going to be quite epic. We are treating How to Train Your Dragon as the first act in a much larger story. As we head into this one, the world expands. Everything is much bigger with still the heartfelt qualities that made the first one resonate so much with audiences. There are no longer restrictions to this tiny island in the North Sea. They have the entire Northern hemisphere within their grasp."
"The only way of tracing the story is to draw on elements that were in the first movie and set up elements for a third movie, so it doesn't feel like a random adventure with the same five or six characters. This truly is a second chapter in a larger story."
Producer Bonnie Arnold added:
"It's going to be more fun adventures with Hiccup and Toothless. There will be some new dragons and maybe some new characters. It's the further adventures of Hiccup on his journey of becoming a man and the ultimate leader of the Viking clan."