|“||When Hiccup and Astrid go away for a weekend, the Edge is attacked by Krogan, Viggo, and their new Dragon Flyers.||”|
While trying to find Hiccup, Fishlegs stumbles upon Hiccup's unfinished secret project covered in tarp, he is tempted to take a peek but it's interrupted when Snotlout asks why Fishlegs is inside Hiccup's hut. Fishlegs explains that Johann has arrived and has requested to see Hiccup, but Snotlout has no clue where he is and says that Hiccup probably doesn't care about Johann because of his growing relationship with Astrid, and that they've begun to spend too much time together alone. They eventually find him at the arena, having a friendly duel with Astrid. Fishlegs informs Hiccup about Johann, and he quickly leaves, along with Astrid, once Johann's name is mentioned. The Riders express their annoyance but are ignored as the couple head to Johann.
Johann sadly informs Hiccup that he is unable to procure the oil he seeks for his secret project, but fortunately Johann gives him a map that tells him he can extract oil from Sassafras plants at a nearby island. When the Riders learn of this, they are unsurprised when the two of them plan on heading out alone. As they prepare to leave, Fishlegs reminds Hiccup that the annual dragon census will begin soon but Hiccup assures him that they'll handle it once they return after a few days, adding further to the deteriorating friendship of the Riders.
While gathering plants for extraction, Hiccup and Astrid discuss the occuring mistrust of the Riders, pondering if their observations are true and that they should head back soon, but ultimately chose not to and decide to take a moonlight flight with their dragons instead.
At dawn, the remaining Riders' sleep is violently disturbed by sudden invading Singetails. Their base is quickly scorched, and Snotlout leads them to combat the Singetails. After an exhaustive fight, they are overwhelmed by the huge numbers, and the Riders fall back with the Singetails in pursuit. Snotlout, having had enough, decides to turn and fight the Singetails, and the others follow his lead, but when the Singetails pass by them, they discover in shock that Dragon Hunters are riding them and enslaving them. Having enough, Fishlegs and Meatlug manage to take down a Flyer, but Fishlegs is thrown off of Meatlug when another one attacks him. Witnessing this event, Viggo strongly suggests that a hunting party be sent for his capture and Krogan decides that he be killed, but Viggo objects, causing tensions between the two. Krogan abruptly obliges, knowing that Viggo is a necessary ally and volunteers to 'capture' Fishlegs himself.
Somewhere on Dragon's Edge, Fishlegs tries to run for cover but he is quickly found by Krogan, riding a huge Singetail, and he orders it to attack Fishlegs. Fishlegs manages to find cover, waiting out the barrage. When Krogan tries to make another run, Fishlegs grabs the opening to try and get through the tunnel, Krogan soon has him in his sights, but luckily Meatlug distracts the dragon enough for Fishlegs to make it inside the tunnel. Krogan manages to regain control of the Singetail but Fishlegs successfully evades him. Once the coast is clear, Fishlegs decides to travel through the tunnel and realizes he's been here before. We can see that it is the cave with the Albino Night Terrors.
Meanwhile, Snotlout, Ruff, and Tuff are defeating Flyers, and realize that Fishlegs was shot down and decide to go find him, but a large flock of Singetails block off their path. They are relieved when Hiccup and Astrid finally arrive and drive the Singetails away, he quickly leads the Riders into another major battle against the Singetails. Krogan arrives with the huge Singetail, and Hiccup almost dies realizing he recognizes him as the bounty hunter who brought him to Ryker in "Midnight Scrum." The relentless attack of the Singetails forces the Riders to fall back to the remote sea stacks of the island, allowing the Dragon Hunters to take over Dragon's Edge. As they settle, Snotlout lashes out at Hiccup for leaving them alone in the island, and Hiccup acknowledges his mistake as it now led to Fishlegs's life being in danger.
As Fishlegs ventures through the dark tunnels, a familiar albino Night Terror lunges at him. He is happy to see Darkvarg, but their reunion is cut short when patrolling Hunters enter the caverns. Darkvarg escorts Fishlegs through the tunnels, while also calling assistance from other Night Terrors to distract the pursuing Hunters. Hiccup, after observing the enemy's activities, manages to pinpoint where Fishlegs is and believes that he isn't captured yet. He prioritizes Fishlegs's retrieval even if it means losing their base to the enemy. When the plan is settled, Hiccup glances at Snotlout in wonder over his quick acquiescence to the plan, and Snotlout expresses his gratitude of having the 'old Hiccup' back and Hiccup thanks him in reply.
Using the cover of night to their advantage, the Riders are able to interrupt the Hunters looking for Fishlegs. Meanwhile, Fishlegs manages to reach the end of the tunnels but his escape is too high for him to reach, and Darkvarg is unable to fly Fishlegs to the exit on his own. But time has run out and the Hunters have arrived, knocking Darkvarg off in one swoop. Fishlegs tries to defend himself but fails and he is forced to his knees as one Hunter prepares to chop his head off. Meatlug hears her Rider's screams and she quickly leads the other Riders in to rescue him, driving the Hunters away. Fishlegs and Meatlug reunite and prepare to fly off, while gratefully thanking Darkvarg.
The Riders regroup, but Krogan arrives at the scene, bringing a huge flock of Singetails behind him. Greatly outnumbered, the Riders have no choice but to ultimately abandon their base to the enemy. But suddenly, Hiccup and Toothless turn back and force their way through, as Hiccup orders Toothless to destroy his hut, along with his unfinished project inside it.
They now seek refuge at Caldera Cay where Mala graciously approves their stay. Hiccup, with help from the Twins, expresses his deep apology for allowing his relationship with Astrid to severe their bonds of friendship, resulting in the collapse of the Edge. Therefore, Hiccup is prepared to regain their trust as they need to focus on taking on the Hunters altogether. Furthermore, Hiccup explains that he destroyed his hut, refusing to allow the Hunters to find his unfinished project. But miraculously, the Riders had actually retrieved it during the early stages of the invasion. With his project exposed, it is revealed that Hiccup was planning on creating a new Dragon Eye on his own.
At Dragon's Edge's volcano, Viggo watches operations taking place on the crater where a mechanical crane is being used to extract something. Krogan, while flying overhead, asks if the Dragon Eye really survived the fall. Viggo replies certain that the Dragon Eye did survive and would soon be in his hands once again.
- Snotlout uses the term "Hiccstrid" for the second time.
- The twins both reference common occurrences about everyday relationships.
- A dragon census is said to be made and is the second such census taken since the beginning of 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
- Michael Goldstrom as Johann
- Adelaide Kane as Mala
- Hakeem Kae-Kazim as Krogan
- Alfred Molina as Viggo Grimborn
- Night Fury
- Deadly Nadder
- Monstrous Nightmare
- Hideous Zippleback
- Night Terror
- Buffalord (mentioned)
- DreamWorks TV Dragons: Race to the Edge Episode Guide. (Copyright 2018.) DreamworksTV.