During their search for the escaped Dagur the Deranged, the Dragon Riders discover a mysterious object.
Dagur escapes prison and Hiccup leads the search for him at a fog-shrouded graveyard of ships; but, while many of the ships hide the treasure of Trader Johann, one ship (the highly booby-trapped Reaper) guards a curious cylinder of unknown significance.—statmanjeff
Learning that Dagur has escaped, Hiccup and his team go off to find and capture him. Dagur, who wants reinforcements, wants Johann's treasures. Hiccup and the team beat him there where Hiccup has to make a tough decision. Save his friends OR capture Dagur