A familiar face joins ranks with the dragon riders, but it's not an easy alliance, especially when Hiccup uncovers a shocking secret about the new member's true identity.

Hiccup, Toothless and the dragon riders rescue a wounded Speed Stinger and take it back to Dragon's Edge, unaware of the dangers that follow.

The dragon riders are surprised to discover who is behind recent attacks on nearby ships – and to learn exactly what the ships are.

Hiccup, Toothless and the dragon riders journey to Glacier Island in search of the Snow Wraith, a fearsome new dragon that holds the key to the Dragon Eye's mysteries.

As a Rumblehorn dragon wreaks havoc on Dragon's Edge, Hiccup seeks the help of Stoick – who forms an unexpected bond with the rampaging beast.

During their search for the escaped Dagur the Deranged, Hiccup and the Dragon Riders discover a mysterious object—one that holds their destiny.

The dragon riders discover a lush island that turns out to be the home of the Deathsong, a massive, never-before-seen dragon that threatens to trap them forever.

Fireworm dragons invade Dragon's Edge, while Ruffnut and Tuffnut discover that they have an unexpected connection to the island.

When Hookfang is drawn to a female Monstrous Nightmare, Snotlout tries to break them up before he loses his best friend forever.

On an island that will make the perfect outpost, the dragon riders discover its indigenous residents are a mysterious new breed of dragon.

When Dagur the Deranged captures young Gustav, it's up to Hiccup, Toothless and the dragon riders to get him back.

Thinking he's allergic to his best friend Meatlug, Fishlegs gets hypnotized – and wakes up transformed into an invincible warrior known as Thor Bonecrusher.

Fishlegs and Meatlug liberate the Gronckles from a menacing new dragon that has encroached on their ancestral home, Dark Deep.