|“||When Hookfang is drawn to a female Monstrous Nightmare, Snotlout tries to break them up before he loses his best friend forever . . .||”|
- Girl-Hookfang makes her debut.
- Snotlout almost gives up being a Dragon Rider in exchange for Hookfang being happy and free.
- Hookfang's Nemesis makes his debut.
The Riders are playing a game they call "Beat the Dome". Hiccup successfully wins. It is Snotlout's turn, and he rides on Hookfang then flies through the forest. However, Hookfang suddenly hears a distant roar and becomes disoriented, much to Snotlout's confusion. After they fly past the forest, they go underground and then finally arrive at the dome. However, they are not fast enough and they eventually crash. The Riders check on Snotlout. He says he is fine, but Hookfang is suddenly gone, so Snotlout begins searching for him.
Hours have passed, but Snotlout is unable to find Hookfang. He eventually finds Hookfang near a cave and attempts to take him back, but Hookfang insists on staying and tries to scare off his Rider by igniting his body; however, Snotlout persuades him and he eventually agrees. The two head back to base. It is feeding time for the dragons, while Hookfang gets his favorite fish, but he rejects it and throws it back at Snotlout. Hiccup tells Snotlout to lock him up in his pen so he will behave. Snotlout agrees. He escorts Hookfang to his pen, saying, "See you in the morning," and leaves to go to bed, sad about his dragon and his sudden change in behavior.
Morning has come, Snotlout has a big bass for Hookfang, and goes to his pen, to find that Hookfang broke out. The other Riders help Snotlout find Hookfang. They eventually find him in the same cave he was when he disappeared the day before. They approach him, but suddenly another Monstrous Nightmare shows up. They identify it as a female. And that explains why Hookfang disappeared twice because he was attracted to the female.
Snotlout tries to get on his back and tells him that he can visit her another day, but before he can reach any further, he blasts him with his fire. Then the other Riders carry Snotlout and return to Dragon's Edge. They discuss Hookfang's current behavior and they figure it out (or so they think): Hookfang is going feral.
Snotlout tells them he will get him to come back. He plans to scare off the female by throwing an electric eel, but Hookfang arrives and tosses it back at his owner. Snotlout then says, "I've had enough of you, Hookfang. It's time to choose her or me." Hookfang sadly chooses his female mate, and, sad because of his decision, Snotlout leaves. He then returns to base and informs his fellow Riders on Hookfang's recent behavior. He tells them that he will just let it be for a while and goes to sleep, thinking he lost his best friend.
The next morning Hiccup gathers Hookfire, Fangmaster and Hookblazefang to replace Hookfang, but Snotlout doesn't like any of them. He tells the Riders that he will quit. Shocked, the Riders try to persuade him not to quit, but Snotlout says that if he can't fly Hookfang, he doesn't want to fly any dragon. So Snotlout tells them that he will say farewell to his dragon and sail back to Berk.
He arrives at the cave to see Hookfang injured. He suspects that the female is the one responsible for it and pulls out a sword and points it at her, and a fight breaks out. Snotlout and the female violently charge at each other, but before either of them can land a blow, Hookfang intercepts them. They show Snotlout some eggs. Snotlout then is frightened, and suddenly a Titan Wing Monstrous Nightmare appears and wants to destroy the eggs. Hookfang tries to stop him but is overpowered and thrown back. Snotlout tries to fight off the enemy dragon with his sword, but Hiccup and the other Riders come to the rescue. The Titan Wing retreats.
They ask Snotlout what is going on. Fishlegs theorizes that the Titan Wing must have heard the mating call and come looking for the female. Tuffnut moronically suggests it's a love triangle, but Snotlout corrects him by explaining that Hookfang is willing to risk his life to protect the female Monstrous Nightmare's eggs from the Titan Wing. Hiccup then theorizes that the call Hookfang was answering was a distress call. Fishlegs theorizes that the eggs the Titan Wing was trying to get at must be the eggs of a rival. Astrid suggests it won't come back but Fishlegs disagrees theorizing the eggs were those of a rival and that it would be back unless it was dominated by another Monstrous Nightmare. The Titan Wing comes back, ready to engage in battle. Snotlout requests the Riders to leave the fight to him and Hookfang.
The two fly into the air to battle the Titan Wing. No matter what the Titan Wing does, Hookfang and Snotlout keep on dodging every attack he makes, a few minutes later they come up with a plan: play beat the dome. The Riders then activate the dome. Snotlout and his dragon then fly to the underground part of the dome to contain the enemy Titan wing, and they could have made it for the first time ever, but they choose to stay inside the dome. Snotlout's plan was to contain them both in the dome (due to the smaller size of Hookfang, they have the advantage), and Hookfang rapidly fires at the big dragon.
The Riders outside are wondering who is winning, then they hear Snotlout saying to open the dome. Once they open the dome they see the Titan Wing, but he collapsed, and find Snotlout and Hookfang standing behind the enemy Titan Wing dragon, leaving Snotlout and Hookfang victorious in the battle and the Titan Wing leaves. Back at the cave, they find the eggs have hatched, while Snotlout and Hookfang are together and happy again.
- This is the second time Snotlout mimics Hiccup, with the first time being in "When Darkness Falls".
- Once again, the twins show a higher level of intelligence, this time with a greater knowledge of theatre.
- Ruffnut stated that she heard that male Vikings fight for female Vikings but she's never seen it.
- This is the first episode where a Titan Wing dragon can be seen.
- Since Hookfang is not really a domesticated animal, he cannot actually go feral. A more appropriate term would be returning to the wild.
- Comparison between Snotlout and Hookfang's relationship becoming strained due to the appearance of a female dragon can be drawn to Hiccup and Toothless' experience in How to Train Your Dragon: The Hidden World.
- 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
- Girl Hookfang
- Hookfang's Nemesis
- Night Fury
- Deadly Nadder
- Monstrous Nightmare
- Hideous Zippleback
- Thunderdrum (mentioned)
- Timberjack (mentioned)
- DreamWorks TV Dragons: Race to the Edge Episode Guide. (Copyright 2018). DreamworksTV.