|“||We release these Singetails all at once. The Flyers go after them. We use the distraction to take out the ground defenses and free the Death Songs. Pretty simple.||”|
|“||After learning Krogan is using a Death Song to lure and subdue Singetails for his growing army of Flyers, the Riders set out to rescue the dragon.||”|
A recent skirmish with the Dragon Flyers causes Fishlegs and Meatlug to accidentally injure a singetail. Snotlout remarks on the fact that the Flyers have seemingly infinite Singetails, and is convinced by Astrid to write a book about the things that only he notices. The Riders tend to the singetail's injuries and notice remnants of Deathsong amber on his body. Astrid worries that Krogan may have discovered Garff's home and she rushes to check him. Fishlegs stays behind to help the singetail recover. They are relieved when Garff remains untouched. Hiccup deduces that Krogan has been using the captured adult Deathsong to exploit its siren that lures and supplies the Flyers with singetails. The riders prepare to return to Dragon's Edge but Astrid pleads to bring a lonely Garff with them. Hiccup argues not to but yields.
The Riders gather to pinpoint known feeding grounds for singetails as it will lead them where Krogan is keeping the deathsong. Astrid marks a group of islands with the best chance but Fishlegs drops the island where the Cavern Crasher is as it would be difficult for Krogan to establish a base there. Before they depart, Hiccup again tries to sway Astrid to leave Garff but she brings him anyway. Snotlout has much to say on this matter for his book.
They eventually find where the Deathsong is kept but after surveying the island, the riders hesitate to launch a surprise attack as it is heavily defended. Garff, however, breaks formation and attacks the island to rescue his surrogate father. Astrid tries to stop him but he is soon overpowered and taken prisoner by the hunters. The riders are forced to regroup lest they risk capture as well.
Fishlegs begins to untangle the Singetail from its chains but it recovers and begins to grow anxious of him. Fishlegs thinks sagefruit will calm it but it refuses. When it becomes too violent to handle, Fishlegs quickly opens the arena and the Singetail flies away. To ensure its safety, Fishlegs and Meatlug decide to follow it.
Hiccup's plan is to use monstrous nightmare gel on the amber-covered Singetails. To ensure that their dragons aren't controlled by the Deathsong's siren, they have them wear makeshift earplugs. Under the cover of night, Hiccup and Snotlout finish pouring a long trail of the gel around the Singetails. Toothless ignites it, allowing the Singetails to break free from their cocoons. Astrid and Stormfly head straight for the shackled Deathsong but are unable to get any closer when the freed Singetails refuse to leave and attack both riders and hunters. Overwhelmed, the riders are force to retreat at a cave. Dragon hunters and flyers converge and surround the cave's only exit point and wait for Krogan's arrival.
Fishlegs's Singetail leads him all the way to the same island where the Deathsong is kept. They sneak past the busy hunters guarding the riders and enter a Singetail hatchery. Fishlegs realizes that the hunters are also letting Singetails lay eggs for further supply and as to why the other freed Singetails refuse to leave. Explosions outside catches Fishlegs's attention as he observes the dragon flyers bombarding another cave as they call for the riders' surrender. Inside, the riders dig in but reunite with Garff when they discover he is also being imprisoned in the same cave. Fishlegs and Meatlug leave the island when he figures out a solution to rescue the trapped riders.
Meanwhile, the besieged riders are left with no plan for a breakout. Astrid regrets her decision to bring Garff, blaming herself for their situation. Suddenly, the cave's walls crumbles when a Cavern Crasher emerges, drawn by Fishlegs and Meatlug keeping him from eating a Singetail egg. Fishlegs intends to use the egg-eating dragon against the hunters but Snotlout points out he has no plan on how to rid of the Cavern Crasher afterwards. Regardless, Snotlout takes up the task of getting rid of the Cavern Crasher and leads it away from the hatchery, unamused by Fishlegs' lack of foresight.
The dragon hunters and flyers are caught off-guard when the riders emerge from another tunnel and begin decimating their defenses. A dragon flyer proceeds to kill the death song but is thwarted by Hiccup and Toothless. The remaining dragon flyers abandon the island. Finally freed, Garff reunites with his adoptive parent, thanking Astrid and the riders before flying back to their home. Fishlegs oversees the safe return of all the Singetails' eggs before they fly off as well.
Back at Dragon's Edge, the riders are impressed by Snotlout's recently finished book, which details his heroic actions that include how he dealt with the Cavern Crasher. Even Astrid acknowledges that the book is very well written. The Twins are worried that Snotlout's book could dethrone their travel-list book as a bestseller and deem his book horrendous. Their comments spur Snotlout to happily redact the Twins' names from his book's acknowledgements, which devastates Tuffnut into crying and angering Ruffnut, much to Hiccup, Astrid, Snotlout and Fishlegs' laughter.
- A recurring gag in this episode is Snotlout writing a book about his adventures, similar to how the Twins were writing about Vanaheim in "A Matter of Perspective".
- The twelfth chapter in Snotlout’s book is titled “The Egg and I”, which is a possible reference to the 1947 film of the same name.
- Singetail eggs are first seen in this episode.
- The Cavern Crasher makes its second appearance in the series.
- Jay Baruchel as Hiccup Horrendous Haddock III
- America Ferrera as Astrid Hofferson
- Christopher Mintz-Plasse as Fishlegs Ingerman
- T.J. Miller as Tuffnut Thorston
- Andrée Vermeulen as Ruffnut Thorston
- Zack Pearlman as Snotlout Jorgenson
- Barf and Belch
- Garff's Adoptive Father
- Mother Singetail
- Firecomb Crasher
- Night Fury
- Deadly Nadder
- Monstrous Nightmare
- Hideous Zippleback
- Death Song
- Cavern Crasher