It is revealed that following the end of the Norvagen/Draigar war, the Dragons briefly returned to Earth but decided to return to Dragon World and let Humans guide their own paths. Scylla, high priestess and queen of the Odaku army, along with her dragon Slann, summons the Shadow Dragons Gryndel and Daakon. She offers to open a portal to the Dragon Realm if they aid her in conquering the Norvagen and Draigar kingdoms.
Meanwhile, Norvagen Prince Dev and Draigar Princess Kyra lead a raiding party to take out an Odaku outpost, who have been increasing attacks against them. But as they enter the outpost, the sleeping soldiers turn out to be decoys, and the raiding party is ambushed. The Odaku wear armour that repels any form of attack and they are armed with explosive weapons. Worse, the Shadow Dragons arrive, and take the souls of Targon and Aurora, Dev and Kyras Dragon companions, killing them. Seeing this, Dev goes into a battle rage. Meanwhile, Dev's and Kyras fathers worry about their children, especially Dev, who has shown signs of being a berserker, like his grandfather. After the attack, Dev and Kyra regain consciousness and find the fallen Targon and Aurora. Dev realizes he is losing control of his emotions. A second fleet of Odaku soldiers arrive and Dev and Kyra are left defenseless. A stranger approaches them and offers to aid them, and Kyra eagerly follows him, along with Dev, who is hesitant about traveling with the stranger.
In the dragon world, King Thoron refuses to interfere in human affairs, which is why they left a second time. But when he hears about the Shadow Dragons, he decides to return and finds Targon and Aurora's bodies. Though the other dragons grieve, Thoron knows that when dragons are killed by Shadow Dragons, they create the cosmic opposite, Light Dragons.
The stranger leads Dev and Kyra through dark caves using an orange dragon crystal. He explains that he is Gorhagar, an Odaku rebel that is heading for the Ramparts of Ryousan to find the Load Stone, a shard of Thoron's dragon crystal, which he will use to find the true king of the Odaku and end Scylla's rule. As they exit the caves, they are ambushed by Odaku warriors. Dev accuses Gorhagar of setting them up and, in a rage, pulls them both over a ledge. Kyra is caught by Slann and brought before Scylla and attempts to negotiate an alliance. But when Dev returns to rescue her, they discover Scylla is in alliance with Stendhal, Thoron's mortal enemy, who is imprisoned in Dragon World. They barely managed to escape with their lives before locating the ancient Odaku city, where Gorhagar, revealed to have survived, and a number of Odaku rebels, who are searching for the Load Stone.
Dev and the rebels hold the line against Scylla's forces before the Norvagen and Draigar armies arrive to assist while Kyra and Gorhagar descend into the catacombs of the city, evading many deadly traps. As Gorhagar revealed that the ancient Odaku king was his ancestor, Kyra realizes that he's the true heir to the Odaku and only he can reach the Load Stone. He succeeds and they return to the surface. In the battle up top, Dev's father is wounded by Slann, causing him to lose control of his emotions again. Thoron, Targon and Aurora, now Light Dragons, have also joined the battle. Kyra manages to help Dev let go of his rage before they help Targon and Aurora Destroy the Shadow Dragons. Scylla takes advantage of their distraction to steal the Load Stone, only to be repulsed by Gorhagar. He and his friends then summons the powers of wind, earth and fire to kill Scylla with molten lava. Gorhagar then presents the load stone to all Odaku, who bow before him as their new king and put an end to all hostilities. Unbeknownst to everyone, Slann's dark spirit, slain by Thoron, secretly enters the portal into Dragon World.
As Targon and Aurora are light dragons, they cannot remain in the living. However, they have managed to produce three new dragons for the three nations. Meanwhile, in Dragon World, Thoron confronts Stendhal and declares him forever banished from Dragon World while Slann, now a Shadow Dragon, watches from afar.Michael Adamthwaite as Dev
Chiara Zanni as Kyra
Michael Dobson as Kron
Kirby Morrow as Gorhagar
Jennifer Hale as Scylla
Ron Halder as Olsef
Richard Newman as Thoron
Scott McNeil as Stendhal, and Gryndel