Alternate universe to the original HTTYD2/3: Nothing prepared Hiccup for the discovery of other dragon riders, or more accurately saying, dragon trappers. Berk and its dragons are all in danger, and the people of Berk alone cannot possibly stand against a stronger foe. Fortunately, there seems to be hope. Astrid caught sight of a lone dragon rider who seems to be following them. They did not attack them, unlike those dragon trappers, so they must be on their side, right? Even if they're not, the least they could do is ask the mysterious person for help in order to save Berk and all its inhabitants.