It is 300 years into the future. Earth's environment had been devastated by mankind's own foolish plans and humankind is beleaguered by the sentient forests which they have awoken. The world balance is tipped when a young boy named Agito stumbles across a machine that glowed in a strange blue hue inside a forbidden sanctuary.
When Lupin heads to the kingdom of Zufu to pilfer its treasure, he incurs the wrath of its psychotic ruler General Headhunter, who places a dead-or-alive bounty on his head.
Shin has shut his heart ever since his mother died when he was young. His childhood friend Kotori has been looking after him ever since. Now that they are in the third year of high school, and it seems like they can finally move forward, another Shin from another Japan has suddenly appeared in front of them.
It's been ten years since the dragons moved to the Hidden World, and even though Toothless doesn't live in New Berk anymore, Hiccup continues the holiday traditions he once shared with his best friend. But the Vikings of New Berk were beginning to forget about their friendship with dragons. Hiccup, Astrid, and Gobber know just what to do to keep the dragons in the villagers' hearts. And across the sea, the dragons have a plan of their own...