Toothless appears as a Night Fury in the franchise, the rarest, fastest and most intelligent species of Dragon there is. He is also the only known member of his species to date. He plays a similar role to his book counterpart.
- "Huh, toothless. I could have sworn you had . . . teeth."
- ―Hiccup names the Night Fury he shot down
As the only Night Fury, he remains elusive, carrying out strategic and lethal strikes against the Vikings' weaponry rather than steal food like the others. Hiccup, needing some way to prove himself to the rest of Berk, successfully shoots Toothless down with his mangler cannon and sends him shrieking from the sky.
During the crash, Toothless loses his left tail-fin, leaving him forever crippled from natural flight. As Hiccup prepares to cut out the dragon's heart to take back to his father once he finds him tied up in Raven Point, he is shocked to see how frightened the mighty creature is.
Hiccup is unable to kill Toothless and instead begins to cut the ropes. Surprised that he is being set free, Toothless rears back, but instead of killing Hiccup, he simply roars loudly at him and then tries to fly out of sight. Toothless' sparing of Hiccup makes him realize that the idea that dragons always going for the kill is wrong.
Despite having escaped from being killed, Toothless finds himself trapped in a cove, unable to fly and therefore unable to escape. Knowing the dragon is still alive, Hiccup discovers the cove and observes him attempting to catch fish and his failed attempts at flying out. Toothless hears Hiccup drop his pencil and stares at him, but remains passive. Hiccup later returns where Toothless is waiting on him. Though suspicious of the Viking, Toothless becomes relatively docile after Hiccup offers him fish.
The hungry dragon takes the offer and regurgitates half of it into Hiccup's lap, deciding to "share" with him. Hiccup plays along and fakes a smile to hide his disgust. Curious about the mannerism, Toothless pulls his face into a confused and comical looking attempt at a smile. Hiccup is awestruck at the dragon's intelligence and reaches out to try and touch him. Toothless is not interested and flies off.
After waking from a nap, Toothless notices Hiccup is still in the cove and curiously looks at the picture of himself that Hiccup is scratching out with a twig. Once again to Hiccup's utter astonishment, Toothless shows his intelligence by drawing a maze of squiggles and lines in an attempt to imitate the boy. Hiccup reaches forward to touch the dragon again, but when Toothless leans back while growling, Hiccup keeps his open hand still and closes his eyes in an act of trust, letting the dragon decide whether to close the gap or not. Amazed by the boy's bravery, Toothless leans his head forward and touches his snout gently to Hiccup's hand.
Hiccup, knowing that Toothless is doomed unless he is able to fly again, begins to work on a new prosthetic tail-fin for him. Their first attempt ends in failure when Toothless realizes that he needs Hiccup to operate it. Over countless test flights, Hiccup designs tail-fin after tail-fin, each attempt bringing the boy and dragon closer. In between these flight tests, Hiccup discovers more of Toothless's playful and curious nature and uses his new found knowledge to his advantage in Dragon Training.
Because of this, Hiccup becomes remarkably popular, much to the annoyance of his fellow Viking Astrid. Now extremely close friends through their interactions, Hiccup and Toothless carry out their first proper test flight. Though temporarily running into a snag, the two snap into focus with one another and instinctively manage to carry out amazing mid-air maneuvers. The flight is a success and both Hiccup and Toothless are ecstatic.
When Hiccup unknowingly leads Astrid to the cove after she is bested in the final test, Toothless shows his protective side by assuming that she is a threat after hurting Hiccup. Only through Hiccup's words does he manage to calm down enough, though he is still wary of her. When Astrid threatens to tell the village of their friendship, Toothless abducts her and strands her in a tree to stop her. Even though Hiccup invites her to a flight to show Toothless is not dangerous, the Night Fury isn't convinced that Astrid can be trusted and pulls off daring moves to terrify her.
After she apologizes, Toothless follows Hiccup's words and smooths out his flight. He gives both Astrid and Hiccup a beautiful "dragon's eye view" of Berk and the beauty of the moment breaks Astrid's long held beliefs about dragons. Unfortunately, Toothless' ties to the other dragons show themselves when he diverts their flight into a huge flock that are carrying great amounts of food. Hiccup and Astrid soon find themselves inside the Dragons' Nest, discovering that the monstrous Red Death effectively holds the dragons hostage with their hauls and devours the ones that don't make satisfactory offerings. Toothless rockets out of the mountain when the Red Death tries to eat him and the trio make a hasty retreat back to Berk.
The next day, Toothless hears Hiccup screaming from afar in the cove. Realizing his human is in danger, Toothless manages to claw his way out of the cove and immediately rushes to Hiccup's side to protect him from the dragon he is supposed to kill. He refuses to leave his friend's side, even when the Vikings eventually get in on the fight and gang up on him. He threatens to kill Hiccup's father Stoick, but only stops when Hiccup yells at him to. This makes the Night Fury let his guard down long enough to be captured. After learning from Hiccup that only a dragon can find the Nest, Stoick has Toothless chained up and used as a compass to find it.
Despite the Vikings' initial sense of victory, the Red Death suddenly bursts out of the Nest and Toothless' ship is set alight. Hiccup, along with the other Vikings on dragons of their own, arrive to save him until the Red Death breaks the ship apart. Hiccup dives into the water in a desperate attempt to free Toothless, but passes out from lack of air. To Toothless' shock, Stoick dives back into the water to break him free and the dragon brings the Viking up to the surface with him. With a roar of encouragement, Hiccup and Toothless team up to take down the Red Death.
The pair soon have the enormous dragon chasing them into the clouds, where the Red Death loses sight of them. As it blows fire everywhere in anger at having lost them, Toothless' prosthetic tail-fin catches fire, leaving them with little time to act. Toothless leads the Red Death to the ground and waits until the larger dragon is about to breath fire before firing one more plasma blast into its mouth on Hiccup's signal. The enormous creature crashes into the ground in a fireball.
Though they try to escape the flames racing after them, the loss of the prosthetic tail-fin leave Hiccup and Toothless unable to avoid a collision with the Red Death's tail, resulting in Hiccup getting knocked off Toothless' back. Seeing his human friend falling to his fiery death, Toothless bravely dives into the exploding body of the Red Death to save him. To Stoick and Astrid's relief, Toothless is able to save Hiccup life by wrapping him in his wings, though is unable to save Hiccup's left leg from damage.
After returning home, Toothless is overjoyed when Hiccup wakes from the battle. Sensing his human's shock at having lost part of his limb, he helps Hiccup to walk with his new prosthetic, the pair of them now equal having lost a part of themselves. After Hiccup discovers Berk has taken the dragons in as companions, Toothless is given a new tail-fin at the end of the film by Gobber and takes off into the skies with his friend once again.
As preparations for Snoggletog begin in Berk, Hiccup loses his helmet during a flight with Toothless. The pair return home where they are bombarded with the news that the island's dragons have all left. Toothless appears to want to follow, making Hiccup feel guilty that he cannot fly on his own. He builds Toothless a new automatic tail so that he can be independent, which causes Toothless to leave just as quickly as the other dragons.
Hiccup, upset that Toothless has seemingly abandoned him, later discovers that the other dragons have left Berk in order to have their babies. Though he is unable to see Toothless on the island they have gone to, he brings the dragons back home as Berk celebrates Snoggletog at last. He questions where Toothless may have gone until the Night Fury returns, attempting to sneak into the hall without being noticed. He is quickly spotted and runs up to his human happily, revealing a drool covered helmet as a gift. Realizing that Toothless had left to try and find his lost helmet this whole time, Hiccup hugs his dragon in thanks.
The next day after waking Hiccup up, Toothless has dragged out the old tail-fin and saddle in anticipation of their flight. Despite Hiccup's protests to stop goofing around as he has his new automatic tail, Toothless proceeds to smash it into the ground and fling it away. He nudges the saddle towards Hiccup, leaving his friend in awe that the dragon would rather fly with him or not at all. As the pair take off and perform a daring freefall, Hiccup remarks how while he may have given his best friend independence, Toothless gave him the better gift of his companionship.
Toothless practically never leaves Hiccup's side during the events of the TV series. It is revealed they now sleep in the same room where Toothless has his own bed made from a slab of stone raised off the floor so he can safely heat it with his flame.
In "How to Start a Dragon Academy", the dragons on Berk run rampant, causing Hiccup and Toothless to try and maintain the peace they worked so hard to forge. After one too many incidents, Stoick, at Mildew's urging, decreed that the dragons would be banished once again. Hiccup and Toothless manage to find a way to use the dragons' abilities to aid the Vikings with fishing and farming. Stoick reverses his decision and gives responsibility of the dragons to Hiccup and his friends. The Berk Dragon Training Academy is officially started to train them.
In "Viking for Hire", Toothless supports Hiccup in his attempts to help Gobber find a new place within the new Viking and dragon community as there was no longer any need for dragon killing weapons. When Hookfang goes on a rampage due to a toothache, the two dragons have a brief scuffle until Gobber managed to discover the cause of Hookfang's behavior and removes the tooth.
During the events of "Animal House", Toothless' protective instincts still show themselves fiercely whenever Hiccup gets into danger, managing to save him from an avalanche and help gain the trust of the surrounding animals.
In "The Terrible Twos", However, this loyalty also shows a jealous streak, as seen when Hiccup discovers a young Typhoomerang whom is named Torch. Jealous of the attention Hiccup gives Torch, Toothless finds that that Torch is just a baby and his mother is enraged with worry. Attempting to take Torch to her directly, Hiccup becomes frustrated with Toothless' behavior and leaves him in the cove as punishment. After Hiccup and the other riders realize what is going on, Hiccup quickly finds and apologizes to Toothless before luring the mother away and returning Torch to her.
As shown in "In Dragons We Trust", after several disasters occurred in the village seemingly caused by dragons, Toothless is blamed for the destruction of the armory. At the villagers' demands, Stoick once again banishes the dragons from Berk, much to Mildew's joy. The riders take their dragons to Dragon Island and are forced to leave them there after several sad farewells. Hiccup vows to be back for Toothless. Toothless waits on the Island for Hiccup to return and keeps the peace between the other dragons in the meantime.
During the events of "Alvin and the Outcasts", eventually, Hiccup does return but as a prisoner of Alvin the Treacherous, who has invaded Berk to capture the 'Dragon Conqueror'. Together, the dragons and Riders manage to destroy the Outcast ship and return to Berk, once more welcome there despite Mildew's protests.
As shown in "How to Pick Your Dragon", Hiccup manages to convince Stoick to start dragon riding. Stoick quickly decides that only a Night Fury is worthy of a Chief and rides Toothless for an entire day, causing him to become exhausted and lonely without Hiccup. Not wanting a repeat the next day but yet respecting Stoick enough to be unable to directly refuse the chief, Toothless hides from Stoick instead. After several disastrous attempts by the other riders to convince Stoick of their dragons' advantages, Toothless is forced to chase down a rogue Dragon, revealed to be a Thunderdrum. Toothless tracks it down and helps the Thunderdrum's friend. Stoick bonds with it with during an attack by boars and everyone returns safely back to Berk.
During the events of "Portrait of Hiccup as a Buff Young Man", Toothless and the other Dragons carried their riders around the island to assist in Hiccup's quest for the treasure of Hamish I. He was the only one who accompanied Hiccup to the final resting place of the treasure as the others had been cut off from them by a cave-in.
As shown in "Dragon Flower", Toothless spends most of his time sick after being been poisoned by the Blue Oleander, along with every other dragon on Berk. Hiccup, Stoick, Gobber and an unwilling Mildew are forced to track down and extract venom from a Scauldron to use as an antidote.
During the events of "Heather Report, Parts One and Two", Toothless and Hiccup encounter the survivor of a wrecked ship, a girl named Heather. While curious about the newcomer, Toothless doesn't see her as a threat and even lets her ride him with Hiccup. When Heather steals both the Book of Dragons and Stormfly, Toothless uses his speed to catch up. Despite trying to get the Book back, Hiccup is subsequently burned by flaming catapults and Toothless retreats, leaving the Book on Outcast Island.
As the dragons and riders eventually reclaim the Book and realize that Heather was only working for the Outcasts because they had captured her parents, they clear things up with her and Toothless lets her pet him before she leaves.
In "Thawfest", during the Thawfest Games, Toothless' competitive side was shown. At first he felt bad for Hiccup, who wasn't doing too well on the first day. On day two, like Hiccup, he let his competitive nature get the best of him. He was just as determined to beat Snotlout and Hookfang as his rider. However, Toothless seemed to understand that Hiccup threw the race and was fine with coming in second.
In "When Lightning Strikes", Mildew tries to convince the Vikings that Toothless' status as a Night Fury was angering Thor and causing various lightning storms to strike the island. It is later revealed to be the metal statue of Thor that attracts the lightning.
As shown in "What Flies Beneath", when holes were found on Berk, it was the only occasion where Toothless has defied Hiccup. A Whispering Death that Toothless had fought in the past comes to Berk. With Toothless attempting to fight his old foe on his own, even ordering the other dragons to stay away from him during the fight, he eventually accepts Hiccup's aid when Hiccup deliberately jumps off a cliff to force his dragon to choose between his human or his long standing vendetta.
During the events of "Twinsanity", Hiccup then attempts to teach Toothless hand signals. While he is fine with "battle ready" and "plasma blast," he remains a little confused with "smile" and "search". However, he was able to fool Dagur the Deranged and his Berserkers during their fake dragon attack.
In "Breakneck Bog", After the riders are looked for Hiccup's lost gift and heard the story behind the dragon doll, Toothless looked touched by the tale, understanding its importance. Toothless then encourages Hiccup that the two go for a night flight.
As shown in "Gem of a Different Color", Toothless helped defend the village from the Changewings who were searching for their eggs.
During the events of "We Are Family, Parts One and Two", During Bork Week, Toothless and Hiccup then journey off, looking for more Night Furies. Though Toothless seems only slightly interested at first, they become excited as they come closer and closer to their goal. Unfortunately, the prospect of other Night Furies turns out to be is a trap set by Alvin and Mildew.
Toothless is locked into a high security cell in the Outcast Dragon containment area. Toothless proves his intelligence when he escapes on his own. He fools the Outcasts into thinking that he is sick and immediately blasts them back when they get close. Notably more violent than he usually is with humans, Toothless' primary concern is finding Hiccup who is missing. They eventually find each other using dragon calls and decide to attack Alvin for what he has done. Both boy and dragon usually refrain from going for the kill, but feel that Alvin has gone too far and dive for him.
It is yet another trap, and they are both temporarily captured by bolas until the other teens' dragons swoop in and rescue them. Back in Berk, Toothless does look slightly saddened to see that the Isle of Night was a fake, but both he and Hiccup agree that there is nothing wrong with being one of a kind. The season ends with Toothless and Hiccup flying off to the horizon, confident that they will be there for each other in the battles that are yet to come.
Months later in "Live and Let Fly", Toothless initially acts very grumpy after Stoick issues a ban on flight. He starts to grate on Hiccup's nerves, trying to convince him to go on their nightly flight and only succeeds in doing so when Gobber talks to Hiccup. Later, he and Thornado combine forces in driving off an attack by Alvin and the other Outcasts.
As shown in "The Night and the Fury", Toothless and the other dragons endure Tuffnut's 'scary' stories while Hiccup and the others are on a training mission. Waiting until Tuffnut falls asleep, they sneak out to find their riders. He is spotted by Dagur who is on Dragon Island with the sole purpose of killing the Night Fury and is hunted by him and, unwillingly, Hiccup across the entire island. When Hiccup decides to end his charade with Dagur, he uses his Dragon Call to call Toothless. Though caught in Dagur's bolas when they try to fly away, Toothless helps Hiccup battle Dagur after initially being forced to watch his human fight on his own.
In "Tunnel Vision", Toothless then meets a dragon who would later become one of his greatest enemies, the Screaming Death. After he and Hiccup escape several Whispering Deaths in their underground tunnel network and drove them out of Berk, he was quickly forced to engage with the Screaming Death who knocks him out of the sky. Thanks to Hiccup's shield and Toothless' speed, along with the Screaming Death's attraction to sunlight, they were able to use the Screaming Death's size against it and force it to crash into a giant sea stack, injuring its wings.
During the events of 'Race to Fireworm Island", Toothless was pitted against Stormfly in a training exercise and was able to evade her by flying into a cave and blending into the darkness, along with Hiccup. Later, when Hookfang fell gravely ill, he helped Hiccup gather Fireworms and saved Snotlout from the Fireworm Queen, when Snotlout stole a fire-comb from her nest.
As shown in "Fright of Passage", Hiccup and Toothless helped Astrid to sneak up on the Flightmare as only a Night Fury had the stealth at night required to do so. He defended the both of them from the Flightmare when it believed its food source to be under attack but as they discovered this, Toothless ate some of its algae, causing him to glow purple. Later, when Fishlegs, Meatlug and Stormfly appeared to help, he cut a new channel for the river to divert the flow of algae out to the sea, forcing the Flightmare off Berk.
In "Worst in Show", Toothless learned a rescue skill that gave him a new way to use his plasma blasts by firing multiple shots as he barrel-rolled. He tried to comfort Meatlug when Fishlegs neglected her, in favor of training his Terrible Terror, Iggy, so he could beat Snotlout in a training competition. Toothless assisted Hiccup in demonstrating Sharpshot's accuracy and, later, used his new rescue skill to destroy Alvin's ship.
In "Appetite for Destruction", Toothless carried Hiccup to several islands that had been mysteriously sunk. It was later revealed that the Screaming Death had returned. It attempted to destroy Dragon Island and was revealed to be behind the destruction of other islands in the area. Toothless and Hiccup managed to hold out long enough for Fishlegs and Astrid to gather as many wild dragons as they could to fight off the Screaming Death.
As shown in "Zippleback Down", Toothless ventured around Berk, disabling old dragon traps left over from the war until Hiccup noticed the hot wind and lack of rain, indicating they were having fire weather. He also helped Hiccup track down the twins, who were trapped in a forest fire and was reunited with Torch, who Toothless was less than thrilled to see again. Toothless and Torch, along with Barf and Belch, were able to use their fire, wings and Torch's abilities to put out the fire.
During the events of "A View to a Skrill, Parts One and Two", Toothless and Hiccup then discovered a frozen Skrill near Berk and hurry to get it off the island, knowing how it is revered by the Berserkers. When the mighty dragon is thawed out, the pair of them face the prospect of a war between the Skrill, Berserkers and Alvin's Outcasts who manage to take the dragon for themselves.
It is later revealed that the Outcasts and Berserkers intend to form a truce between themselves, using the Skrill as their weapon of choice to invade Berk. Though the two groups eventually fall out with each other, Toothless and Hiccup manage to seal the Skrill back into its icy prison and avoid a potentially deadly battle.
As shown in "The Flight Stuff", Toothless carried Hiccup on scouting runs to Outcast Island so that they could see what Dagur was up to but during one of these scouting missions, Hiccup and Toothless were captured and nearly killed, due to Gustav and Fanghook's interference and eagerness to help. However, Snotlout and Gustav managed to use their Dragons to free them while Astrid and Stormfly distracted the other Outcasts.
During the events of "Free Scauldy", Toothless and Hiccup, along with the other members of the Dragon Flight Club, started searching for the Screaming Death as they decided it was too dangerous to leave unchecked. When they passed Changewing Island, they discovered an injured Scauldron, which rebuked all their attempts to help it, even though it would have died if left out of the water too long. Toothless, Meatlug, Barf and Belch refused to leave it and, eventually, they were able to help it by lifting the rocks off of its wing when it took a liking to Ruffnut. They managed to fix the Scauldron's wing with a large makeshift splint, which Ruffnut cut off her braids to finish.
In "Frozen", after being stuck inside a shelter, due to a massive snowstorm, Hiccup and Toothless went on a Search and Rescue mission for Trader Johann. Toothless used his Echolocation to great effect across the frozen sea but, shortly after they left Berk, they almost collided with the Speed Stinger Horde. After finding Johann during the night, they returned to Berk during the day to find the village mysteriously empty. He searched for the Speed Stinger nest, along with the other Dragons and their riders, so that they could capture the Alpha and use it to lure the Horde away from Berk. Toothless engaged the Alpha in one-on-one combat and, with Stormfly's help, managed to force it into a cage. Later, he carried it across the sea after Stormfly got stung carrying it and got paralyzed, luring the horde away from Berk. Afterwards, they flew Johann back to his ship so he could continue trading.
As shown in 'A Tale of Two Dragons", Toothless spent most of his time with Hiccup, helping to sort out Mildew's old cabbage field and trying to break up Stormfly and Hookfang when they were fighting each other, only for Toothless to start fighting too. Eventually, they discovered the cause of the aggression was Dragon Root, which Meatlug was immune to, and threw it into the ocean.
In "The Eel Effect", Toothless eats an eel by mistake while trying to save Hiccup and becomes very sick, attacking Hiccup and shooting his fire randomly everywhere. When Toothless sees that he has hurt Hiccup through his sickness, he runs off. When Hiccup and Fishlegs find Toothless, a huge blue Typhoomerang attacks and events eventually lead Toothless to run off a cliff edge out of control. Hiccup quickly puts his foot into the stirrup and tries to control Toothless, the dragon refusing to let him on. Hiccup and Fishlegs manage to ensnare Toothless long enough to give him the medicine for the eel. He regurgitates the eel and returns to normal.
During the events of "Smoke Gets in Your Eyes", Toothless then sensed that something was very wrong with the pile of scrap metal that Gobber bought from Trader Johann but, nevertheless, helped get it to Gobber's forge at the blacksmith request. The next day, he and his rider woke up to find out that the entire village had been robbed of a great deal of metal objects and they both, along with Astrid and Stormfly, investigated the scenes of the crimes, to no result.
Later, in the night, Hiccup was attacked by adolescent Smothering Smokebreaths, who were attracted to his metal leg and Toothless helped to fight them off, before going to tell the others. After setting a trap, they followed the Dragons to their nest, only to find out that the entire situation had been orchestrated by Dagur, who was on the horizon with his armada. To end this threat, Toothless carried all the metal the village had left, along with the other Dragons, and threw it at the Armada so that the Smokebreaths would steal all the components from Dagur's ships causing them to sink. He then helped lure the Dragons to Johann's boat, who was making a stop at Breakneck Bog.
In "Bing! Bam! Boom!", Toothless and Hiccup, along with Stoick and Thornado, discovered three baby Thunderdrums out at sea and, unknowingly, led them back to Berk, where they started causing havoc and disaster. Toothless and the other members of the Academy tried to train the three Dragons but it turned out that only Thornado could control them and so Toothless and Hiccup, as well as Fishlegs and Stoick, left them on Dragon Island after several failed attempts. They found out that the other Dragons on the island had chased them out to sea in the first place and so Toothless, Meatlug and Thornado fought off several Dragons of different species to defend the hatchlings. Afterwards, Toothless carried Hiccup and Stoick back to Berk since Stoick had left Thornado behind to look after the hatchlings.
- Astrid: "For what it's worth, I always knew red was your color."
- Hiccup: "Aww, Astrid, thank you."
- Astrid: "I was talking to Toothless."
- ―Astrid and Hiccup
During the short that explains the formation of Dragon Racing, it is revealed that Toothless' preferred color for the event is red, matching his and Hiccup's attire.
During the events of "Dragon Eye of the Beholder, Parts 1 and 2", three years have passed since the war with the Berserkers. Toothless and Hiccup fly out in the hope of searching for new lands and dragons but to no avail. After Johann was fished from the ocean, Toothless went with his rider and the other riders to the Ship Graveyard in an attempt to capture Dagur. Once there, Toothless went with Hiccup to take a look at The Reaper, where they found the Original Dragon Eye. They were then confronted by Dagur and his Berserkers.
After Hiccup gave up the Dragon Eye to Dagur in exchange for being allowed to save his friends, Toothless then tried to blast the cage open, but to no avail. Despite this setback, Hiccup's friends were saved and Toothless was able to retrieve the Dragon Eye from Dagur. Toothless then went with Hiccup, Gothi and the other riders to Glacier Island. There they fought the Snow Wraith in order to get one of it's teeth to unlock the Dragon Eye. After they returned to Berk, Toothless was able to use his fire to light the Dragon Eye.
As shown in "Imperfect Harmony", Toothless was present when Hiccup showed the Dragon Eye to Stoick and the other members of the Berk Council . After giving his son permission to leave Berk, Stoick entrusted Toothless to take care of Hiccup, which the Night Fury grunts in agreement. They soon reached a beautiful island where the Riders stop to rest. The next morning however, the dragons were gone. Toothless later found Hiccup and the others, telling them the other dragons were in danger.
In a rush, Toothless grabbed Hiccup's metal leg and accidentally yanked in off without even knowing. Once realizing that he had only the prosthetic, he returns it to his rider, with a guilty look. After chasing off a wild Thunderdrum, the Riders encounter a new dragon, the Death Song, and learn that it draws in dragon with its song, then traps them in its amber blasts to eat them later. While the Riders were trying free their dragons, Toothless faced the Death Song, only to get caught, as well as everyone except Hiccup. Using the Monstrous Nightmare gel Snotlout brought, as well as the aid of the Thunderdrum from before, Hiccup freed everyone, and trapped the Death Song in a cave.
In, "When Darkness Falls", the Dragon Riders finally found an island to use as their outpost. Like Hiccup, Toothless was not fond of the other Riders arguing over designs for their base. When the duo, along with the twins, discovered the Night Terrors and captured their leader, they returned to the others. They soon realized the small dragons are defenseless without their alpha's guidance. Toothless and Hiccup return the leader, which Tuffnut named Smidvarg to his pack and chase off the Changewings that were threatening them. After finally deciding a design for Dragon's Edge, the Night Terrors become the island's sentries. Smidvarg gather the pack together to form a giant Night Fury as a sign of their alliance, much to Toothless' enjoyment.
As shown in "Crushing It", Toothless then assisted the rider in their attempt to capture a wild destructive Rumblehorn. However, with Stoick's help, Toothless realized that the Rumblehorn was trying to warn them of a tidal wave coming towards the edge.
In "Quake, Rattle and Roll", Toothless then went with Hiccup, Fishlegs and Meatlug to Dark Deep. However, once there they saw that the Gronckles had been pushed off by a Catastrophic Quaken. Toothless was unable to force it to leave, but then watched as Meatlug and Fishlegs made friends with it and the Gronckles.
During the events of "Have Dragon Will Travel, Parts One and Two", Toothless then helped the riders track down a rogue dragon and it's rider . Toothless was able to shoot the dragon and it's rider, who revealed herself to be Heather. Toothless was then able to follow Heather to Trader Johann's Ship, where he and Hiccup forced Johann to give him information on Heather's next target; Dagur.
Toothless then saved Heather and Windshear from Dagur's chains and escaped, back to the Edge. There, Toothless told the other dragons to back off from Windshear. Toothless then helped Hiccup convince Heather to not kill Dagur because he was her brother.
As shown in "The Next Big Sting", Toothless then watched Hiccup tested his prototype Flightsuit. He saved Hiccup from crashing in the first two tests. Toothless, along with a Speed Stinger, Speedy, were able to force his pack to leave the edge.
During the events of "Team Astrid", Toothless and Hiccup then searched for Dagur after he attacked Berk. However, he and the other dragon and their riders came under attack at the Edge by Dagur's fleet. However, they received help from Astrid, Stoick and the Dragon Riders' Auxiliary.
As shown in "Night of the Hunters, Parts One and Two", Toothless and Hiccup then saved Astrid from drowning following Stormfly's kidnapping by the Dragon Hunters under Ryker Grimborn. However, they were defeated and had to retreat. Later, Hiccup came with the idea of using Screaming Death scales as armor for Toothless and Hookfang, protecting them from the Dragon Root Arrows. The plan worked and they saved all the riders.
In Bad Moon Rising, Toothless, Hiccup, Fishlegs and Meatlug go to Lycanwing Island in search for the mythical dragon. However, they found out that the Lycanwing was only an invention to keep humans away from a Dragon Eye Lens. Also, when Tuffnut fell off a cliff, Toothless was the one who caught him.
- "You never cease to amaze me, bud. Thank you . . ."
- ―Hiccup, sharing a moment with Toothless
By the second movie, Hiccup and Toothless have taken to exploring the areas beyond Berk as well as experimenting with new glide-suit that Hiccup has developed to allow him to fly alongside the Night Fury. They have nearly perfected the art of their flights, but not enough to stop them from crashing after another unsuccessful test. After teasing Hiccup with the threat of throwing him off the cliff edge, Toothless play fights with Hiccup and 'defeats' him with multiple licks to the face. After Astrid arrives on Stormfly, Toothless plays with his dragon companion whilst Hiccup and Astrid talk about the future.
Hiccup notices a mysterious plume of smoke rising in the distance and Toothless flies him to the sources of the smoke, along with Astrid and Stormfly. There, they encounter Eret and his dragon trappers, managing to escape from their ruined fort with news of a mysterious dragon thief and the notorious Drago Bludvist. Though Stoick commands that Berk be locked down when he learns that Drago is coming, Toothless and Hiccup fly off in defiance twice, even when he tells the duo that Drago cannot be reasoned with.
During their flight, Toothless shows visible worry at his human's frustration with his father before they are approached by the dragon thief. As a horde of dragons under the thief's control steal Hiccup from his back, Toothless plummets to the icy ground and vainly tries to fly after Hiccup. He is soon swarmed by aquatic dragons and taken to the thief's Sanctuary.
Though protective of Hiccup, Toothless is left docile by the thief's abilities. She reveals herself to be Valka, Hiccup's long lost mother and she shares her 20 years experience of dragon secrets with them. On a particular flight where Toothless enjoys a big mouthful of fish, she reveals a series of hidden "spikes" on Toothless' back that he can subsequently extend at will to increase his maneuverability in the air. Toothless later watches happily as Hiccup, Stoick, and Valka reunite and plan to become a family once again on Berk.
The reunion is cut short when Drago and his Bewilderbeast appear and attempt to destroy the Sanctuary. After killing the former Alpha, Drago orders his Bewilderbeast, now the new Alpha, to seize control of Toothless. Though he tries to resist, no dragon can resist the Alpha's command and Toothless becomes entranced. Unresponsive to any of Hiccup's words, he advances relentlessly towards his human to kill him. As Toothless prepares to fire, Stoick jumps in the way to save his son at the cost of his own life. Toothless is temporarily freed from the Alpha's control and tries to approach Hiccup and Stoick, unsure of what has happened. In his pain and grief, Hiccup yells at Toothless to get away. Hurt at his friends' words, Toothless flees the area, allowing Drago to use his Bewilderbeast to take control of him once again. Toothless leads Drago on his back to lead the assault on Berk.
Drago arrives at Berk, ordering the Alpha to freeze the island. Hiccup and the other riders, returning home by riding the baby Scuttleclaws that are outside the Alpha's control, arrive to stop him. Still mocking Hiccup's beliefs in training dragons, Drago allows Hiccup a chance to 'talk' to Toothless. Hiccup assures his dragon that Stoick's death wasn't his fault and the Alpha's control begins to slip.
As Hiccup pleads with Toothless to come back to him, the bond between human and dragon allows Toothless to break free from the Bewilderbeast's control and throw Drago off its' back. Trusting Hiccup to blindfold him to resist the Alpha's call, Toothless pulls off a daring immelman that allows Hiccup to get Drago away from the Alpha. However, despite seemingly having won the battle, The Alpha then freezes both Toothless and Hiccup in a prison of ice.
The ice suddenly blows apart and Toothless emerges not only having protected Hiccup, but glowing blue with pure energy and having evolved into a rare Titan Wing. Enraged at the attempt on Hiccup's life, Toothless subsequently challenges the Bewilderbeast directly, breaking its hold on the other dragons with relentless fire attacks and rallying them to aid him.
As he and Hiccup give Drago one last chance to back down, Toothless orders the other dragons to use their fire on the gigantic beast and eventually breaks one of the Bewilderbeast's tusks off, forcing it to flee. With Berk saved from Drago's onslaught, the assembled dragons all acknowledge Toothless as their new Alpha and the Titan Wing Night Fury joins the celebration of Hiccup being made the new chief of the village.
When a rampaging Thunderclaw runs through the village with Snotlout on its back, Hiccup and Toothless attemps to calm him down. However, they only manage to get Snotlout off, as the Thunderclaw continues to run towards some children. Hiccup and Toothless then separate and the Night Fury turns into his Alpha mode, finally stopping the Thunderclaw. Toothless then plays with the children Hiccup saved.
Toothless then watches how Hiccup argues with some villagers about Eret and becomes angry when they try to attack his owner.
On their way to Nepenthe, the riders are accompanied by Tidal Class dragons which bring Toothless fish as a sign of respect for yheir new Alpha. He is very happy about this, as he eats fish from a Scauldrons mouth, then flies graciously above some Thunderdrums.
On Nepenthe, Toothless accompanies Hiccup as they meet Mik, the king of the island. Toothless then relaxes in one of the many hot pools of the island, despite Hiccup wanting him focused on the task.
At dinner, Toothless, along the other dragons feast on the various food, but they all quickly collapse. Calder then appears and captures all the dragons and riders.
After Hiccup escapes, he brings Toothless in his Alpha mode, along with the other dragons and the riders prepare to leave the island. However, right then, some Foreverwings wake up and began destroying the village. Hiccup and Toothless attempt to calm them down and succeed after Toothless turns into his Alpha mode. He presumably tells the dragons to leave the island. He and Hiccup are then attacked by Calder who is using Hiccup's Inferno. While Toothless growls in the background, Hiccup throws a canister of Zippleback gas a Calder, killing him.
The next day, Toothless is seen along Hiccup when he offers Mik a shovel. He then assists at Hiccup's speech to Berk. In the Great Hall, Toothless jumps on a tired Hiccup, distracting him from his thinking. While at first Hiccup is mad, he then scratches Toothless and the book ends.