|“||As Hiccup and Snotlout race to rescue the others from the Dragon Hunters, they don't realize that someone close to them is working for the enemy.||”|
Astrid, Fishlegs, and the Twins sit in their cell feeling very shocked that Heather had betrayed them and that she and Dagur were in league with Ryker and the Dragon Hunters. As they question how Heather could put loyalty to her brother ahead of loyalty to them after all they had done for her, Astrid tells them that the real question is who are the Dragon Hunters and what do they want from them.
Heather then comes by with two Dragon Hunters, they open the door before Heather shoves Astrid out and the Dragon Hunters close the door. As Heather shoves Astrid down the corridor with the Dragon Hunters following behind them, Astrid reminds her former friend on how she and the Dragon Riders had taken her in, had taught her to ride a dragon and saved her life more than once. Although Heather thanks her for all that, she still says she has to follow her destiny and that tells Astrid that she doesn't know what it's like to be truly alone and that she trusts her brother with her life as he would never hurt her. Astrid tells her she would regret it but Heather tells her to worry more about herself. She knocks on the door on Ryker's headquarters and after it opens, with no choice Astrid walks inside without hesitation before Heather goes inside too.
On a different island, as the sun rises, Hiccup, Snotlout, and their dragons wake up before Toothless goes to get some fish from the sea nearby. After he brings them up, when Snotlout tries to eat some of it, Hookfang keeps taking the fish and eating it himself. Hiccup unfolds his map of the Dragon Hunter ports to try and track them down but Snotlout reminds him that even if they find the Hunters, their dragons would surely be shot by the Dragon Root dipped arrows. As they struggle on how to shield their dragons from the arrows, Hiccup says they've got some hard riding to do and they take off on Toothless and Hookfang.
Back on Ryker's ship, in their cell, Fishlegs and the Twins are sleeping when a Dragon Hunter comes by and pushes Astrid back into the cell before closing it again. She tells her friends that she was questioned all night mostly by Heather and Dagur but all Ryker did was stare a lot. When it all seems to Ruffnut that Astrid didn't talk at all, Astrid tells she did talk much to Ruffnut's anger. Astrid explains that she told Ryker the location of the Dragon Eye; she then explains that the Dragon Hunters have been looking for it for a long time. As Ruffnut asks her where she told them it was hidden, Astrid whispers that she answered it was back at Dragon's Edge being guarded by the other Dragon Riders they had left behind while a Dragon Hunter from outside walks by. Tuffnut then comments that no one is supposed to know about it, Astrid answers that she knows while trying to keep the tone down. After realizing that they had to go along with her, Fishlegs remarks that Dragon's is like a fortress before Astrid remarks that it was under the command of "Captain Gustav" as another Dragon Hunter walks away from their cell. As Tuffnut asks Astrid, why "Captain Gustav" outranks him, Astrid tells him it was the only thing she could think of to keep them from sailing in and taking over Dragon's Edge.
However when it all seems to Ruffnut and Fishlegs that Astrid's plan had worked and that it had bought them some time, Astrid answers that the plan had worked, for now, however, Ryker would send someone to check it out and that they had to get off the ship before they found out, she was bluffing. When Tuffnut tries to think of an idea to escape the cell and the ship, he thinks of an idea to tunnel through the bottom of the boat into the middle of the sea much to Astrid and Fishlegs' surprise and annoyance.
Meanwhile far away, Snotlout and Hiccup are flying over lots of islands while Snotlout keeps asking: "Is that the island we're going to?" but Hiccup keeps replying "no" the whole time until they finally come to the island that Hiccup says they must head to. After they land on the island, Snotlout moans and asks Hiccup why he didn't tell him they were going to an island full of Whispering Deaths. Hiccup replies that he knew Snotlout would react exactly like he was now and that someone else lives on the island as well. The ground suddenly shakes and out of the earth comes the Screaming Death. Toothless and Hookfang growling at the large dragon as it looks at them, the Screaming Death doesn't seem to recognize them and charges towards them. Hiccup tries to calm Snotlout down when he tries to explain that the Screaming Death will calm when he comes closer and recognizes them as they reunited him with his mum years ago but still, the large dragon keeps charging a roaring at them so Toothless and Hookfang take off with their riders into the clouds. Hiccup tells them to go right once they're near the light, they follow Hiccup's orders and when they're out of sight, the Screaming Death hovers in the air looking for them. Although it seems to Snotlout that Hiccup's plan is to flee once they escape the giant dragon, Hiccup tells him they have to go into the Screaming Death's tunnels as there is something they need. They head back down to the island and then into the tunnels.
Back in their cell, Fishlegs and the Twins are still arguing on how to escape their cell. After a lot of squabbling and fighting, Fishlegs grabs Tuffnut's cup and throws it out of the cell. They try thinking of other ideas such as Fishleg's plan to get the guards to like them hoping they would lower their guard and Tuffnut's idea to use acid to cut through the bars. However, they dislike each other's ideas while Astrid comments that Tuffnut's plan would not work any more than Ruffnut marrying the guard, divorcing him and getting the key in the settlement plan. Heather then comes by and tells them that Ryker wants to see them and orders them out, as they walk out Astrid barges on Heather's shoulder. With Heather and Dagur by the sides of a corridor, Ryker walks through and tells the captured Rider's that they are his prisoners on his ship and their dragons are now his dragon while Dagur comments that their dragons get treated is entirely up to them.
They are then showed their dragon's tortures: Meatlug is cruelly being fed boulders and is forced to make metal for Dragon Hunter armour, Dragon Hunters are pretending to attack Stormfly making her what to shoot her spines at them meaning that they can be used to make spears and blisters with them while Barf and Belch are having their skin polished while being distracted by fish so that their skin can be made into Zippleback boots. Ryker tells them that this is what happens to their dragons if they don't give him some real answers. He demands that they tell him what they know of the Dragon Eye and how many "Riders" guard their base, however, the Riders still refuse to give them answers. When it all seems to Ryker that they will not go for his plan, he orders the Dragon Hunters in Barf and Belch's cell to keep polishing their skin so it will be ready to sell. Ruffnut pleads for her and Tuffnut's dragon to not be harmed while wrapping her arm around a Dragon Hunter's body and slipping down. She then stands up and still refuses to give Ryker some information, Ryker then orders his men to put the Riders back in their cell.
Back in the Screaming Death's tunnel, Hiccup and Snotlout are still flying through them on Toothless and Hookfang. Hiccup mentions that if the Screaming Death grew bigger, it means that it had to molt as there should be old scales. They find some old white scales however Snotlout mentions that his thinking is the worst plan ever and tells him that it might not work as much as his 'Let Meatlug get captured' plan didn't. Hiccup tells him that they have to get as many scales as they can before a large roar echoes along the tunnel. Hiccup then tells Snotlout to get as many scales as he can out of the tunnels just before the Screaming Death appears in front of them. However, before the Screaming Death can fire, a Whispering Death appears behind them and roars at the Screaming Death ordering it to stay away from the Riders and their dragons. Hiccup recognizes the other dragon as the Screaming Death's mother and as he pets her, he tells Snotlout to get the scales fast.
In their cell, while Astrid is looking outside the cell door, Fishlegs and Tuffnut are still arguing about how they can escape. Astrid then turns around and tells them she has memorized the guard schedule and that she has a plan but they need a way to get the door open. Ruffnut shows them a key that she had stolen from a guard. When Astrid asks how she got it, Ruffnut tells them that when she squeezed the Dragon Hunter guard, she actually sneaked the key out of his boot when no one was looking, much to the others' surprise. Astrid tells them that once she takes out the guards, they split up to get their dragons and then blast off the ship and out of the range of the arrows. After secretly unlocking the door, she calls for the guard that she'll tell Ryker what she wants to know in order to save her dragon. A guard comes forward to unlock it but with the door unlocked without him knowing, Astrid pushes the cell door against the Dragon Hunter knocking him unconscious. Just before another guard comes in, Astrid closes the cell's door to make it look like nothing happened, and as the other guard checks the Hunter she knocked out, she pushes the cell door again and knocks the other guard unconscious too.
Before they split up to get their dragons, Astrid tells them to be careful because there could be booby traps anywhere like on the Reaper. They then split up in different directions; a moment later Fishlegs reunites with Meatlug. As he checks the metal that Meatlug was forced to make, he realizes that it is Gronckle Iron and that the Hunters must have the formula so he decides to look at the rocks Meatlug was fed. Astrid dashes through Stormfly's cage and is able to dodge a trap lever before she can step on it; she and Stormfly happily hug each other. Ruffnut and Tuffnut arrive to save Barf and Belch in their cage but their dragon is only interested in eating more of the fish. Ruff and Tuff try to reach their dragon but when Barf and Belch's tail whish at them, Tuffnut accidentally steps on a trap lever causing a bell sound to ring and alert the Hunters. Back in Meatlug's cell, Fishlegs tries to find the last ingredient but a Hunter comes by and takes him away. Back in the other cell, Ruffnut and Tuffnut try to pull their dragon out of the cell but two Dragon Hunters point their crossbows at them. In Stormfly's cell, Astrid tries desperately to undo Stormfly's chain but Heather comes in and tells her she is not going anywhere. Astrid picks up a spear nearby and prepares to fight Heather before Heather unfolds her double axe and closes the cell door with it.
- It is revealed that the Dragon Eye used to belong to the Dragon Hunters.
- Fishlegs manages to figure out the recipe for Gronckle Iron, thanks to the Dragon Hunters.
- The Screaming Death returns and is confirmed to be male.
- Heather and Astrid were never seen fighting each other when they were alone. The reason for this is revealed in "Snow Way Out".
- Snotlout is revealed to be excellent at stitch work, which his mother taught him.
- When Tuffnut questions Astrid about how Heather managed to beat her, she says that Heather had an axe while she didn't, or a mace, sword, or crossbow. Astrid did, however, have a spear, though she doesn't mention it.
- The mention of Tuffnut not being able to swim may be a reference to how Fishlegs can't swim in the books
- The Northern Markets are mentioned for the first time.
- 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
- Mae Whitman as Heather
- Gustav Larson (mentioned)
- Snotlout's Mother (mentioned)
- David Faustino as Dagur the Deranged
- JB Blanc as Ryker Grimborn
- Viggo Grimborn (mentioned)
- Night Fury
- Deadly Nadder
- Monstrous Nightmare
- Hideous Zippleback
- Screaming Death
- Whispering Death
- Screaming Death Island
- Unnamed Islands
- Northern Markets (mentioned)
- Dragon's Edge (mentioned)
- Dragon Hunter Island (indirectly mentioned)
- Hiccup's Prosthetic Leg
- Toothless' Saddle and Tail Fin
- Dragon Armor
- Astrid's Improvised Weapons
- Astrid's Kransen
- Heather's Axe
- Heather's Horn
- Heather's Dragon Eye Lens
- Dragon Hunter Weapons
- Dragon Hunter Ships
- Gronckle Iron
- Dragon Eye (mentioned)
- Zippleback Boots (mentioned)