
Set 1,300 years after the events of How to Train Your Dragon, dragons are now just a legend to the modern world. When a geological anomaly opens an immense, miles-deep fissure in the Earth’s surface, scientists from all over the world gather at a new research facility to study the mysterious phenomenon. Soon a group of misfit kids, brought to the site by their parents, uncover the truth about dragons and where they’ve been hiding -- a secret they must keep to themselves to protect what they’ve discovered.






Moving to an exotic new home, an adventurous teenager meets a new group of kids and discovers a dragon in the fissure.
Tom forges a friendship with the dragon and discovers an entire world of dragons within the fissure.
Tom and Jun encounter unexpected dangers and are separated while exploring the Hidden Realm of dragons. Tom introduces Jun to the dragon world, and Jun bonds with a dragon of her own – Wu and Wei.
Tom and Jun take a risk in revealing the secret of the Hidden Realm to D'Angelo to aid an injured dragon, and D'Angelo bonds with Plowhorn.
Tom and the others debate how to keep the dragons a secret, even as a rambunctious young "cloaking" dragon gets loose in town and pursues a friendship with a reluctant Alex.
Tom and the Riders try to save ICARIS when it's revealed to be in danger from a monstrous dragon.
Jun breaks the rules by sneaking a small dragon out of the Crystal Realm and bringing it home.
Tom distracts his mom while the riders use a new dragon to close off a cave.
When Feather is taken by a group of zombie dragons, Alex finds her inner hero to rescue her friend.
Tom and Thunder train a new species of tidal dragons to help the other riders put out a forest fire.
Tom and D'Angelo must come together to help Alex and Jun escape the clutches of the Spiderwings.
Tom and the riders go in search of Thunder and face dangerous dragons; Tom reveals his big secret.
Tom and the riders help Thunder, who is seeking revenge against dragons that chased off his family.
Tom hatches an unorthodox plan to use a Monstrous Nightmare to test Alex's new fire suit, endangering the secret of dragons.
After a fight with her mom, Jun joins Tom on an adventure into the Fire Realm, where her knowledge of myths saves the day.
When a tiny Fireworm dragon ends up at ICARIS, Alex must decide between her mom's excitement and keeping the dragon secret.
During an attempt to get displaced Fire Gronckles back to their native realm, D'Angelo accidentally feeds them Catastrophic Quaken eggs.
Much to Jun's chagrin, Eugene finally discovers the secret of dragons and demands to become a Rider, but he must bond with a dragon before he's let into the group.
When the Riders discover that Magma Breather is very sick, the only way they can help is to sneak the huge and heavy dragon into the ICARIS infirmary without being caught by any of the scientists.
The Sky Torcher and Flame Throwers invade the Crystal Realm; Tom must conquer his demons and bond with the Fault Ripper to defeat the Sky Torcher.
The Riders discover a brand-new, frosty Ice Realm; once inside, they encounter a disguised Buzzsaw.
Alex and Eugene find themselves at odds with Tom and their fellow dragon riders.
Jun struggles to convince Tom to trust her faith in myths over the Book of Dragons.
Eugene questions Tom's leadership abilities when Tom's decisions lead to failure.
Tom and Thunder discover a baby Night Light and must bring him back to Thunder's home realm.
Tom and the Riders vow to help Thunder face the dangerous dragon who attacked the Kings Realm.
While grounded at home, Tom must figure out how to help the Riders without getting in more trouble.
Tom orchestrates a "safe" tour of the Realms for Olivia, but things don't go as planned.
When a mischievous new breed of dragons steals the Book of Dragons, the Riders must get it back.
After Eugene is captured by a dragon and taken to her nest, the Riders must rescue him.
Tom must save Olivia from the Hidden World when she goes exploring on her own.
The Riders must use the dragons to get the humans through a deep freeze without being seen.
Tom struggles under the pressure of being the new Dragon Whisperer for Rakke Town.
D'Angelo and Eugene get locked in the hangar with the dragons when the parents leave for the night.
Jun struggles to be taken seriously for her love of myths and forms a connection with Sledkin.
Eugene and Webmaster's bond is tested when Webmaster abandons him for a pack of Deathgrippers.
The Riders discover that an explosion in the Hidden World injured a dragon and follow their suspect.
D'Angelo struggles when the dragons fall victim to Buzzsaw's poison darts.
After Buzzsaw injures a water dragon, the Riders go against their parents' wishes.
When Phil threatens to shut down D'Angelo's new dragon hospital and ban dragons from ICARIS, D'Angelo and a little Hobgobbler have to change his mind.
While Tom struggles with admitting his feelings for Jun, the pair find themselves trapped inside a giant tree with an anxious colony of Woodchipper dragons.
Thunder must wrangle and lead the Hero Dragons in a desperate attempt to save Tom and the riders from a dangerous new dragon, The Glass Caster.
When Jun does a Tarot reading for the team, she interprets its meaning to be that the riders will disband! In an effort to defy this fate, Jun forces the group to stick together as they search for a dragon that has breached the Rakke Town eel barrier.
With the dragon riders disbanded, Eugene attempts to start his own Dragon Club.
When Thunder accidentally fries Alex's tablet, Alex goes off on her own and is captured by Buzzsaw.
Tom and the riders must finally overcome their differences and come together as a team to survive the Dark Realm.
In order to defeat Jörmungandr, the World Serpent, Tom must learn to emulate Hiccup.
Tom and the Dragon Riders foster displaced Hidden Realm dragons in Rakke Town, but things get hard.
The Dragon Riders enlist Carla and Hazel's scientific knowledge to help them neutralize Jörmungandr.
Tom and the Riders must rescue Plowhorn from Sledkin when the villain abducts the dragon.
Tom's overconfidence turns to frustration as he struggles to build a trap to stop the World Serpent.
A major miscalculation by Tom jeopardizes the fate of the Realms.