Opening sequence, Princess Celestia assigns our heroes to go to a village called “Berk.” To help a guy named, Hiccup Horrendous Haddock III. But she doesn’t exactly give the descript of what the mission is. But adds that the mission is a test. Later, Twilight breaks out in song “The Failure Song” Then our heroes set off for Berk, but they decide to pick up a few more characters to go with them. (And on the way, 3 dragons join up with them)
Movie segment: How to Train Your Dragon is centered around a teenage Viking named Hiccup (voiced by Jay Baruchel) who lives on the island of Berk with the rest of his tribe. Over the course of seven generations, Berk has been continuously raided by dragons of all different species, prompting a war between them and the tribe. Like every other young Viking on Berk, Hiccup is expected to fight and kill a dragon in order to be considered a true Viking. However, he is very small for a Viking his age, can hardly lift and use traditional Viking weapons, and has a tendency to cause accidents. His father Stoick the Vast (voiced by Gerard Butler), who is also chief of the tribe, tries to keep Hiccup indoor as often as possible.
During one particular attack on the village while working his post in Gobber's (voiced by Craig Ferguson) smithy, Hiccup decides to prove himself as a Viking and capture a dragon using his own methods rather than standard Viking brutality. Using a bola shot from a cannon he designed and built himself, Hiccup is overjoyed when he hits a dragon in mid-air, thinking it's the rare and dangerous Night Fury. Having not paid attention to in the chaos, no one else in the village believes him because no one ever even saw a Night Fury, yet alone brought one down. Hiccup goes to the forest at Raven's Point to bring back the dragon's heart as proof to Stoick. Meanwhile, Stoick and Gobber discuss Hiccup's behavior, after a meeting is held in the main hall, and how to make him into a proper Viking. Although initially hesitant, Stoick agrees to enlist his son into Dragon Training in the hope it will toughen him up and give him survival skills before preparing to lead an expedition to take out the Dragon's Nest.
Despite being told to go home, Hiccup disobeys his father and heads out to the forest (along with our heroes). He searches for some time but can't find where the dragon went down. Luckily, Hiccup finds a broken tree and churned up ground, leading him to the downed dragon which is tied up in the bola shot. He psychs himself up in preparation to cut out the dragon's heart with his belt knife. The ponies earge Hiccup to do it but after Hiccup sees the fear in the helpless dragon's eyes as it looks back at him, he can't bring himself to kill it. After cutting it free from the ropes, the Night Fury pounces on him and the situation is now reversed: Hiccup is clearly afraid and the dragon stares intently into his eyes for several moments. When it rears up, Hiccup cringes as he thinks it's going to kill him, but it instead roars angrily in his face before attempting to fly off into the trees. Hiccup attempts to walk away, but faints from the encounter. While everyone else is confused of why the Night Fury didn’t kill him.
On the first day of Dragon Training, the other students, Snotlout, Fishlegs, Ruffnut and Tuffnut make fun of Hiccup after being nearly killed by a Gronckle, but is saved in the nick of time by Gobber. As Gobber stows the beast away, he mentions a dragon "will always goes in for the kill". Hiccup and our heroes return to where he found the Night Fury, wondering why it didn't do the same to him. Following the path the dragon flew off to, Hiccup notices half of the Night Fury's tail was torn off in its crash and can't exit the small cove which it became trapped in. Attempting to finally record actual information about Night Furies, Hiccup drops his pencil and alerts the dragon to their presence, but the Night Fury only stares at them. Later that night, Hiccup reads the Dragon Manual in hopes to learn more about the creature, but it only says the Night Fury is extremely dangerous.
After barely surviving a Deadly Nadder in Dragon Training shortly afterwards, Hiccup attempts to get closer to the Night Fury by offering a fish. The dragon's attitude, on guard after spotting his belt knife, greatly improves after Hiccup tosses it away in the cove pool to prove his intentions. (Some of the team even place their guns down away from their current location and the equines reluctantly do the same) It cautiously takes the offering of fish using its retractable teeth and regurgitates some of it to share with Hiccup. To stay on good terms, Hiccup takes a bite of the raw fish (now covered with dragon's drool), and is forced to swallow with some disgust as the dragon watches expectantly, and is surprised to see the dragon attempt to imitate a smile. However, his attempts to touch the Night Fury cause it to fly off to the other side of the cove. Later that same day while attempting to sleep, the Night Fury is curious Hiccup hasn't left and walks over to see the boy drawing an outline of the dragon's head in the dirt. Curious about the drawing, the dragon snaps off a large tree branch and attempts to do the same, making deep impressions in the ground of random scribbles to try to draw Hiccup's head. Hiccup is amazed by it and when the dragon growls when he steps on it, takes care not to stand on the drawing before finally getting close enough to the Night Fury to touch it. It still doesn't allow him to do so, but when he only holds his hand out, palm open and leaves it to the dragon to decide, it presses it's nose into it.
Hiccup continues Dragon Training along and continues to prove he is unable to accomplish even the most simple tasks necessary to fight dragons. One night after such a battle, Hiccup learns from Gobber a dragon without its wings can't fly, explaining why the Night Fury can't leave the cove. The engines then talk to the equines about their behavior around the Night Fury whom they name “Toothless” due to the retractable teeth. But the equines are shocked that they decided to name the dragon. (“Put that thing back where it Came from or So help Me”) Hiccup attempts to get Toothless, to fly again through the use of an artificial tail fin. It soon becomes clear after a test run the design needs improvements and Toothless can't fly on his own. Through testing new versions of the fin, Hiccup learns things about dragons from experiences with Toothless. He pushes a Hideous Zippleback into its cage through learning the dragon's distaste for eel, incapacitates a Gronckle using knowledge of Toothless' love of garlic grass, or "Dragon Nip", leads a Terrible Terror into its cage by having it chase a beam of light like a cat, and incapacitates a Deadly Nadder by scratching it below the chin. The Viking adults see these feats of "subduing" dragons without actually harming them as a sign of greatness. The other Vikings teens watch in awe as Hiccup improves his skills, but Astrid's rivalry turns into extreme jealousy. Shortly after, Hiccup perfects his design of the prosthetic fin and helps Toothless take a successful flight around the island. After taking a lunch break with several wild Terrible Terrors, Hiccup realizes everything the Vikings know about dragons is wrong. Soon enough, the engines then realize what the mission Princess Celestia gave them was, ‘To show that not all Dragon are bad!” However, the equines, and Terence, [save Zecora] still refuse to accept Toothless as a friend and still think that he could kill them when he gets the chance, but then Stuingtion’s Engines then explain reasons of why Toothless wouldn’t try to harm them. (“Good Inside”)
As Hiccup becomes popular with his technique of incapacitating dragons rather than killing them, Astrid notices his strange behavior of leaving after every session. After losing out on the right to kill their first dragon in a final test, an angry Astrid follows Hiccup and our heroes to the small cove where Hiccup plans to leave Berk with Toothless to avoid taking part in his final exam. Toothless, thinking Astrid is a threat, attempts to attack her and subsequently exposes Hiccup's relationship with the dragon. In an attempt to keep Toothless a secret, Toothless pulls Astrid onto the top of a tree and Hiccup offers her a ride on the dragon's back to show her he means no harm. Astrid reluctantly accepts Hiccup's offer, but a cautious and annoyed Toothless fakes extreme attempts to throw her off. After Astrid admits she's sorry for what she tried to do, Toothless stops his acrobatics and takes them on a calming romantic flight above the clouds. Astrid's view on dragons is changed and she comes to think Toothless is amazing. (our heroes are flying behind in their planes)
Hiccup, Astrid, and our heroes are surprised when Toothless changes course and flies alongside other dragons that carry food to their Nest. Toothless follows them and hides as Hiccup, Astrid, and our heroes discover the dragons aren't eating their kill themselves. Instead, they feed it to the Red Death, a gigantic Seadragonus Giganticus Maximus. The dragons are forced to feed the Red Death with what they steal from Berk or else they will be eaten by it instead, as proven with an unlucky Gronckle and a Hideous Zippleback. The dragon then try to get some of the equines but Toothless saves them, making them finally accept Toothless as a friend.
After they escape the Nest and return home, Astrid wants to tell Stoick and the village about the Nest, but Hiccup is adamant that she not do so, otherwise they would kill Toothless. Shocked, she asks in disbelief if he would go that far to "protect his pet dragon". Unlike the uncertain and hesitant Hiccup she's always known, Hiccup looks right at her and tells her "yes", causing her to see him in a new light. Astrid promises to keep Toothless a secret and punches Hiccup in the shoulder for "kidnapping" her before kissing him on the cheek for "everything else".
Stoick returns from his unsuccessful attempt to find the Dragon Nest and is surprised to hear how well Hiccup does in Dragon Training. His son is placed into his final test to become a Viking: kill a Monstrous Nightmare in the battle arena. Instead of killing it however, Hiccup tries to tame it to prove the dragons aren't dangerous creatures. His father's insistence of killing the dragon makes the Monstrous Nightmare revert into its regular state into attacking Hiccup. Toothless hears his human friend's cries of fear and help from the cove and rushes to save him, climbing out of the cove by himself and running through the forest. Astrid enters the battle arena in an attempt to save Hiccup, but fails to fight off the Monstrous Nightmare. Stoick helps Astrid get out of the arena but Hiccup is stopped short when the dragon blocks him from escaping. Toothless arrives in the nick of time and saves Hiccup by fighting away the Monstrous Nightmare. The other Vikings are in awe at the Night Fury and jump into the arena to capture him. In defense, Toothless attacks the Vikings, including Stoick, to stop them from harming his human friend. Hiccup tries to order Toothless to leave before he is captured, but Toothless' strong devotion to protecting Hiccup causes him to stay put. Hiccup barely stops Toothless from using his fire on Stoick before the Vikings eventually overwhelm him. Hiccup tries to explain to his father dragons are nowhere near as harmful as they think they are, but Stoick refuses to listen, outraged his son befriended his enemy. During his attempt to explain, Hiccup accidentally mentions the Dragon's Nest and says only a dragon can enter the Nest, giving Stoick the idea to use Toothless as the ticket to get there. Hiccup tries to explain again to his father why the Dragons were so fierce when they took the Viking's livestock, attempting to mention the Red Death and it's treatment of the dragons. Stoick refuses to listen and simply says to Hiccup that he is no longer considered his son.
The Vikings prepare themselves and leave to fight the dragons, keeping Toothless chained up aboard one of their ships. Hiccup watches them leave from the village's harbor as Astrid encourages him to do something. Asking why Hiccup didn't kill Toothless, Hiccup explains he saw Toothless was as afraid as he was and realizes the mess he caused from being the first Viking in 300 years who wouldn't kill a dragon. Astrid's words convince him to take action and get back Toothless. He teaches the other teens how to ride the arena dragons, then fly their way to the Dragon's Nest. (As the team contact Blythe and pets for extra help)
The Vikings reach the Nest using a shackled Toothless as a guide, then use catapults to blow a hole in the Nest's lower base. Upon doing so, the dragons flee from the enraged Red Death, causing it to break through the side and attack the Vikings, setting all of the longboats on fire, including the one Toothless is chained up on, leaving them with no escape. Stoick realizes the scale of the fight Hiccup tried to tell him and curses himself as a fool. He, along with Gobber, decide to sacrifice themselves to let the others escape. However, both them and the Red Death are halted in their efforts when Hiccup and his friends arrive on dragon's back and shoot at the back of the Red Death's head. Hiccup instructs Snotlout, (riding the Monstrous Nightmare), and Fishlegs, (riding the Gronckle), to go to the Red Death's blind spot and make noise to keep it confused while Ruffnut and Tuffnut, (riding the Hideous Zippleback), (and our heroes are in their planes, now joined by Blythe Baxter and the pets in The Littlest Pet Jet) exhaust the Red Death's shot limit and Astrid, (riding the Deadly Nadder), drops off Hiccup so he can free Toothless. However it turns out Fishlegs and Snotlout can't find a blind spot due to multiple eyes on the side of its face but they continue to bash the shields, this works on the Red Death but also works on Fishlegs' Gronckle and Snotlout's Monstrous Nightmare. The Nightmare flings Snotlout onto the head of the Red Death while the Gronckle drops altitude. Fishlegs, before crashing, throws Snotlout his hammer which Snotlout uses to hit the Red Death's eyes so it doesn't step on Fishlegs. In the Red Death's thrashing about in steps on the boat Hiccup and Toothless are on and Toothless sinks a few feet below water. Hiccup still tries to save him but passes out from lack of air. Stoick, amazed at what Hiccup and his friends did, dives down and saves them both. After apologizing to his son, he tells him he doesn't have to face the dragon, but with a smile Hiccup replies "we're Vikings: it's an occupational hazard", something Stoick said early in the movie. Telling Hiccup he's proud to have him as his son, Stoick watches as Hiccup climbs aboard Toothless and heads toward the Red Death. Astrid instructs the twins to get Snotlout off the Red Death's head which they do. However, Astrid is almost sucked in and eaten by the Red Death until Toothless and Hiccup stop it with a plasma blast. Astrid falls off her Nadder due to the force of the plasma explosion but Toothless catches her. After dropping her off Astrid silently says "go".
Hiccup angers the Red Death into following him with Toothless using a powerful plasma blast. After leading it up high enough into the dark clouds, they hide among them and while diving past at high speed, repeatedly blasting hole after hole into the Red Death's wings. (our heroes help Hiccup and Toothless along too with their planes) In pain and anger, the giant blasts a long stream of fire all around it, setting Toothless' prosthetic tail-fin alight when the Night Fury can't avoid the flames. Knowing they have little time left, Hiccup dives nearly straight down, the Red Death in hot pursuit. When he hears the sound of the Red Death heating its gasses to fry them, he waits for the last possible moment, then shouts to Toothless; Toothless spins around and fires a plasma blast directly into the Red Death's mouth, prematurely igniting the gas and setting its insides on fire. Our heroes then fire a barrage of bullets at the Red Death’s wings in order to render them useless. Toothless twists away and slips past its head, as it realizes its about to hit the ground. However, when it spreads it wings to stop itself, all the holes in its wings tear into even bigger holes, rendering its wings useless.
As the huge dragon crashes at full speed and explodes, Hiccup is knocked off unconscious when Toothless is unable to turn away from hitting the Red Death's tail after his prosthetic fin burned. Seeing Hiccup fall towards the flames beneath, Toothless dives into the inferno of the Red Death's exploding body to save him. After smoke from the battle clears, it is shown Toothless survived, with his prosthetic fin destroyed and his saddle empty and burned. Everyone believes Hiccup was killed in the explosion, reducing Stoick to tears. He apologizes, saying how sorry he was for not listening to his son. Toothless sees this and unfurls his wrapped up wings, revealing he has an unconscious Hiccup clutched to his body: his fire-proof dragonhide saved Hiccup's life.
After about three weeks, Hiccup wakes up in his bed, which has been placed on the main floor at home, surprised Toothless is in his house to joyfully greet him. As he gets out of bed, after being licked by Toothless, he discovers he lost his left foot and lower shin (as Toothless was unable to fully enwrap those parts with his wings), which was replaced by a prosthetic made by Gobber. After taking a moment for the feelings of sadness and loss to pass by, Toothless helps him walk outside and where both of them are surprised to see the Vikings invited the dragons to live in the village. Hiccup is welcomed back as a hero and Astrid punches him for "scaring her" and gives him a kiss on the lips. Then Princess Celestia and Princess Luna show up and tell our heroes they’ve succeeded in their mission and passed the test, which was “To try and befriend dragons rather than try to harm them or kill them.” As they are given another assignment to hang around Berk and learn more about the dragons and how to befriend different species of them. (which leads to Thomas & Twilight Sparkle ride Dragons: Riders of Berk) After Toothless is fitted with a new fin and saddle that Gobber built, Hiccup, Astrid, and the other Viking teenagers ride their dragons through Berk as the new age of a Viking and dragon alliance begins ("The Success Song").
In the credits plays the bloopers reel,
In a post credits scene, the play "Put That Thing Back Where It Came From Or So Help Us" is shown.
- Zecora, Stephen, Sharky, Mako, Willy, T.C., Hugs, Buzz, J.J., Socky, Skunky, 1206, The Miner Trains: (Steam Grindor, Steam Mech, Mucker, Steam Claw D., Steam Driller, Steam Sweeper, and Steam Exavator), Evan, Steamy, Puffy, Shai-Shay, Rattlesnake Jake, The Planet Trains: (Zip, Dazzlen, Dusten, Gustis, Rings, Uray, Tune, and Shiver), Dusty Crophopper, Bill and Ben, Duke, Mrs. Calloway, Maggie, Grace, Ord, Cassie, Zak and Wheezie guest star in this film.
- This film marks the first appearance of Bill and Ben's plane: "The Twin Wings"
- Princess Celestia and Princess Luna will appear at the beginning and end of this film.
- Blythe Baxter and pets make a climax appearance in this film.
- The storyline continues in Thomas and Twilight Sparkle show How to Train Your Dragon 2.
- Princess Celestia's mission
- Opening/Dragon attack!
- The downed Night Fury
- Forbidden Friendship
- Later that night/A new tail for Toothless
- Improving Toothless' flight and dragon skills
- Test flight
- Lunch break/discovering the mission
- Talk with Stoick/"Good Inside"/final dragon
- Astrid founds out/romantic flight
- The Dragon's den
- Hiccup's final test/Toothless to the Rescue!
- Stoick confronts Hiccup/The Vikings set off for the den
- Hiccup rallies the others/at the den/the Red Death unleashed
- Battling the Red Death
- Bloopers Reel/The post credits scene: "Put That Thing Back Where It Came From Or So Help Us" play