It's the story of a young Viking. Actually, he isn't that young anymore. He's 23 years old now. His name is Hiccup Horrendous Haddock III. 8 years ago, he had to run away from his beloved home Berk because he became best friends with a creature that no Viking should ever become friends with: a dragon. Follow the brave...
It's been days after the battle of the Red Death. Days since Dragons and Viking united and days since, the young boy, Hiccup was gravely injured defeating the Red Death. He's recovering well. His life is okay for now. Has a good relationship with Astrid and the other teens. But everything changes when he discovere...
Same as any other. A fifteen year old Hiccup runs away, well, rather he flies, from Berk. Because He couldn't kill the Monstrous Nightmare in front of the Village, and he saw no other option. But he will return to Berk unexpectedly.