|“||Hiccup grows wary when Gruffnut arrives on the Twins’ 19th birthday to administer a Thorston coming-of-age ritual involving three dangerous challenges.||”|
As Ruffnut and Tuffnut's birthday approaches, the Twins prepare for an initiation trial in order to be accepted into the Thorston family. As the Twins prepare for a celebration, their cousin Gruffnut appears on the Edge unannounced. With him being untrustworthy, the Riders lock him up until they can decide what to do with him. When he reveals that his purpose is to administrate the trials, the Twins release him. However, Gruffnut tells them only one can become a full-fledged Thorston. The Twins find they can't separate each other and forfeit the trials.
Gruffnut then goes to the Twins and gives them lies in order to get them into the trials. There was to be three stages, the first one being to grab a bottle of Speed Stinger venom. When the Twins realize they are both in the trials, they become competitive and try to beat each other. As they are both successful in the trials, they move on to the next challenge.
The next challenge was to retrieve a molten Changewing skin in which you could use to camouflage. By using the Speed Stinger to paralyze the Changewings, both the Twins came back successful once more.
The final trial was to get a chest of treasure from a cave. The cave was actually a Titan Wing Zippleback nest. Using the skins of the Changewing the Twins navigated through the cave undetected. When they both arrived at the treasure, they realized how they had separated and their relationship was lost. They each tried to sacrifice their family right for one another, but eventually were caught. Cornered, they ran through the cave to where the others awaited. As they opened the treasure chest, it was found to be empty of treasure, and instead full of rocks and potatoes.
Because both the Twins completed the trials, they were not let in. As Gruffnut left, another Thorston, called Agnut, arrived, only to reveal that she was the one who was giving the trials, and Gruffnut never completed them himself.
As Gruffnut sailed off, he opened the chest to find a secret compartment where a Dragon Eye lens was hidden.
- Jay Baruchel as Hiccup Horrendous Haddock III
- America Ferrera as Astrid Hofferson
- Christopher Mintz-Plasse as Fishlegs Ingerman
- T.J. Miller as Tuffnut Thorston / Gruffnut Thorston
- Andrée Vermeulen as Ruffnut Thorston / Agnut Thorston
- Zack Pearlman as Snotlout Jorgenson
- The way Tuffnut and Ruffnut use the molted Changewing skins is similar to how the Invisibility Cloak is used in the Harry Potter franchise. It is also similar to how Bilbo Baggins used the One Ring to avoid being seen by the dragon Smaug in The Hobbit.
- The title is a play on the phrase, "A Rough Separation".
- Though birthdays have been mentioned before, this is the first time characters are actually seen celebrating them.
- As of this episode, all 5 of the class dragon lenses have been found.
- Titan Wing Hideous Zipplebacks make their debut and are revealed to be extremely territorial.