Snotlout is sent on an undercover mission to Viggo's dragon auction as part of a plan to rescue the dragons and stop Viggo from getting richer.
When Viggo offers Hiccup a truce, the wary Dragon Riders investigate and find a potential ally in their fight against the Dragon Hunters.
Heather's brother Dagur shows up out of no where and asks Hiccup for help finding her. He wants to learn to ride dragons. Dagur sees Heather on the edge and goes the extra mile to protect her.
The dragon riders take a dragon egg from the dragon hunters and they try to train the baby dragon. Will they be able to do it?
Viggo is building an impenetrable fortress that even dragons can't break through, it's up to Hiccup and the gang to stop him.
When Hiccup and Toothless are kidnapped and Toothless is forced to fight other dragons for entertainment, the rest of the dragon riders must save them before it's too late.
When things don't go well while Fishlegs is in charge, he gets another chance to prove he has what it takes to be a leader.
While trying to take care of unfinished business, Hiccup and Toothless are lured into a trap. An unlikely rescuer comes to their aid.
After learning that Fishlegs has been secretly communicating with Heather, the gang invites her to the Edge to convince her to join the Dragon Riders.
After Astrid makes an alarming discovery, her life comes to depend on a dragon everyone thought was extinct. Her pals race against time to find it.
When the Dragon Riders fly to an island on a vacation, a small creature there has a special effect on the dragons.
When a mysterious dragon attacks Spitelouts storehouse, Spitelout and Stoick have different ideas on what to do next.
A wounded Fireworm seeks the Dragon Riders' help in protecting a precious treasure trove from an unfamiliar creature with strange and slimy powers.
Harvey imagines himself and his friends in a magical steampunk world, but things come crashing down when Harvey is blamed for breaking a floating city
A wounded Fireworm seeks the Dragon Riders' help in protecting a precious treasure trove against an unfamiliar creature with strange and slimy powers.
When things get out of hand while Fishlegs is left in charge, he seizes another chance to prove he has what it takes to be a leader.
Hiccup's and Snoutlout's fathers put aside their differences and work with their sons as a team to defend a storehouse against an unusual invader.
Hiccup reluctantly allows the Dragon Riders to go to a deserted island for a much-needed vacation, but the getaway has an odd effect on their dragons.