The Dragon Riders come across Speedy after Hiccup failed in testing his flight suit. Due to his injury, Speedy is aggressive towards the group and paralyzes Ruffnut. However, he slowly warms up to them and accepts their help. The Dragon Riders decide to take Speedy back to Dragon’s Edge for a full recovery, unaware that their action attracts the entire Speed Stinger pack.
Speedy becomes accustomed in living on the Edge, and he also reveals that his species has evolved webbings in his feet to travel across the archipelago. Snotlout is not pleased in having Speedy around, so he and Ruffnut decides to fly the young dragon back to his island. When the sun sets, Speedy wakes up and paralyzes Hookfang. When the Speed Stinger pack reaches the Edge, the Dragon Riders struggle to protect each other. Speedy becomes inspired by their cooperation and kindness and starts to protect the Riders from his own pack. He eventually convinced his Alpha to leave the Edge and says his farewell to the Dragon Riders before chasing after his pack.
Speedy appears very similar to other members of his kind, except the Alpha. He is lime green with a tan underbelly. He also has lime green fins and stubby wings. Like other members of his species, his stinger is red in color. Unlike a typical Speed Stinger he along with the rest of his pack have webbed feet.
Speedy was, at first, very skittish and vicious, attacking the riders when they tried to help him. However, later on, he became very protective of the riders, who, at this point, he considered his pack. He defended them from the other Speed Stingers from his pack, even going as far as directly disobeying his alpha. He even wanted to stay behind with the riders, but Hiccup convinced him to return to his pack.
He is also playful and affectionate as he licked Snotlout's face, much to Snotlout's disgust.
Speedy possess all the abilities of a Speed Stinger and of his pack:
Speed: Speed Stingers are renowned for being the fastest dragon species on foot.
Webbing: His pack needed a way to island-hop so they evolved in a way that provided them with the ability to run on water using webbed feet.
Sting: Because Speedy is still an adolescent, he can only cause partial paralysis in his victims, as his sting potency is not at full effect.
Hiccup was the first to meet Speedy as founded to be wounded. As Speedy shown to be very aggressive just like typical Speed Stinger but Hiccup didn't want to leave this baby Stinger alone thinking will die from its injuries. Hiccup was able to get some trust to Speedy by showing trust and it was working as Speedy as proven that the teens and their dragons to be pack.
Speedy has shown good relationship as Speedy was listing to Fishlegs commands little bit as he was showing to have good bond because Speedy is having new pack to listen well. But Speedy still stung Fishlegs on his arm but still had great bond.
Meatlug have shown to like Speedy as it was baby dragon that she shows some mothering to him, as she was trying to nudge Speedy to get him to train with Fishlegs. She was even trying to save Speedy from running on water, as she assumed he will drown since they are unable to swim. However, the riders have found out they can swim in the water, much to Meatlug's shock.
Speedy didn't like Snotlout at all due to being mistreated by him many times by his comments, because his hatred of Speed Stingers and what their kind have done to Snotlout stuns him in the past. But Speedy still shows some respect to him because they are in the same pack, as Speedy will defend Snotlout from his old pack.
Speedy and Hookfang didn't shown to interact munch but Hookfang might not like Speedy munch as he was bit scared of Speedy by getting loose from the ropes and stung him down to the ground. Like Hiccup stated that Speedy was part of the Edge Pack as he will protect the riders from harm as it possible Speedy will defend Hookfang since he is member of the pack.