The episode opens showing a scene of a Monstrous Nightmare and Deadly Nadder as they fly through the sky above Berk. Everything seems fine, until the two dragons, not paying attention, crash into each other, starting a fight above a small farm. The sheep, terrified, attempt to run from them, but only bump into one another, due to being trapped in a pen. Bucket and Mulch arrive, and chase the dragons away, before returning to their regular duties of milking and gathering eggs. Bucket lifts a hen off of her nest, but discovers she wasn't sitting on an egg. He asks Mulch if chickens lay eggs, and Mulch irritably asks him if they need to go over which purpose each animal serves. Bucket replies he hasn't forgotten, but quickly proves he is lying, by lifting a sheep and checking to see if it laid an egg. Mulch points out each animal, stating the sheep provide wool, the chickens lay eggs, and the yak provides milk. He tries to demonstrate the proper way to milk the yak, but when he attempts to milk her, she doesn't give any.
Meanwhile, Astrid and Hiccup are in the mountains, having a 'Dragon-boarding' race, in which they slide down the mountain slopes on their dragons. When Astrid pulls ahead, Stormfly launches some of her tail spikes in an attempt to make Hiccup and Toothless slow down. In retaliation, Hiccup and Toothless pull ahead, and Toothless extends his right wing, blocking Astrid's view, and making it impossible for her to dodge a branch filled with snow, which hits her in the face. She protests, but Hiccup cheerfully feigns ignorance, saying he has no idea what she is talking about. Stormfly lets out a burst of fire, which melts a pile of snow in front of Hiccup and Toothless, causing them to temporarily spin out of control. Hiccup hears a rumbling noise behind them, and turns around to see they started an avalanche. He attempts to take off with Toothless to escape, but is horrified to discover his prosthetic tail fin froze shut. The avalanche gains on them, and Hiccup tries to warn Astrid. She turns around to look, and takes off on a berm of snow, unaware of the danger her friend is in. Hiccup leaves Toothless' saddle and climbs towards the prosthetic fin, attempting to manually pry it open, but fails to do so. Astrid notices they rapidly approach a large abyss. She turns around and attempts to help Hiccup, despite his protests telling her to go back. Unable to fly away, Hiccup and Toothless drag Astrid and Stormfly into the trench with them, the snow trapping them inside. When Astrid and Hiccup wake up, it's completely dark, and Astrid says she is freezing. The two huddle together for warmth, and discover their dragons are still with them, working together to burn a hole in the ice until daylight filters into the trench. Hiccup and Astrid discover while they were unconscious, their dragons protected them, by blocking the snow with their wings, creating a makeshift room that prevented them from being crushed. The dragons watch them with endearing looks, and the two quickly separate from their embrace, embarrassed.
A few hours later, Bucket and Mulch called on the assistance of Stoick and Gobber, who examines the yak. Gobber concludes she isn't giving milk. In way of explanation he tells Stoick a story regarding his mother and his goat, and how the goat was also unable to give milk, much like the yak, because she was afraid of his mother. He states the animals aren't laying eggs or giving milk because they're afraid of the dragons, who are around more often, due to the war between Vikings and dragons ending. Moments after Gobber's conclusion, Bucket clamps his hands onto his bucket and cries out in pain. Mulch asks him if his bucket is getting tight again, and Bucket tries to deny this, but another wave of pain interrupts him. Mulch explains to Stoick that Bucket's bucket tightens when a storm approaches, the storm being worse the tighter it gets. He comments the bucket is incredibly tight, predicting a terrible storm. Bucket says he doesn't like storms, because he might get struck by lightning and wind up being even less intelligent. At Stoick's disbelief a storm could hit so early in the season, Mulch reminds him the bucket predicted the Blizzard of Olaf. Stoick and Gobber dismiss this, not wanting to judge the weather based on the tightness of a bucket. The two go to visit the elder Gothi for a second opinion, relying upon her expertise; namely weather prediction via chicken bones and goose feet. They inquire about the storm, and Gothi draws strange figures on a smoothed patch of dirt, while Gobber interprets them for Stoick. Gothi's reply is a short, 'What do you think?', leaving them to guess for themselves. She directs their gaze at her house, and it's boarded up, sand bags piled up by the door. They take this to be a 'Yes', and ask her how she knew, the goose feet, or the chicken bones. She writes another message, and Gobber tells Stoick she heard Bucket's screams all the way from her house, proving the bucket is accurate in predicting the weather.
At the top of one of Berk's defensive catapult towers, Hiccup and Astrid sit with Fishlegs and Snotlout, recounting what happened. They state it was almost as though it were the dragon's instinctive nature to protect them. As Hiccup and Astrid comment on this, they're oblivious of how close together they sit. Fishlegs states they could have used their body heat to stay warm, which brings their attention to where they sit. Once more, they're embarrassed, and shift away from each other. Snotlout, trying to either tease or flirt with Astrid, asks if she is still cold, offering a hug. Astrid rejects him by elbowing a support post, causing a snow drift from the catapult to fall on him. Ruffnut and Tuffnut arrive to deliver a message to Hiccup, saying his dad needs him, and seems to be angry. Hiccup notes his father looked like that since the day he was born, and sarcastically states he's sure the two things have no connection.
Hiccup and Toothless arrive at home, to discover Gobber and Stoick request his assistance to help the animals get over their fear of the dragons before the winter storm comes. If the village becomes snowed in, they won't hunt or fish for months, leaving them dependent on the livestock for their survival. Hiccup repeats his father's earlier statement, saying they're still in the middle of winter, and devastating winter isn't due for another month. Bucket and Mulch report in with an empty milk pail, saying they still got nothing after trying to milk one yak for three hours. Hiccup protests the dragons aren't trying to be scary on purpose, and they don't even eat farm animals; they eat fish. Gobber points out to him dragons are also large, fire-breathing reptiles, which frightens the animals. Hiccup agrees and is at first given a week to fix the issue before the storm comes, but when Bucket cries out in pain again, Mulch recalculates the storm's arrival to be in three days and six hours.
The next day at the Dragon Academy, the teens rounded up all of the livestock in Berk, and attempt to show them dragons aren't dangerous. They first try to show the animals dragons are friendly, attempting to see the dragons from their perspective. Fishlegs goes so far as to go on his hands and knees and walk around, making sheep noises. Upon seeing a Monstrous Nightmare from the position of a sheep, he also admits the dragons are scary, and hides behind Meatlug. The trainers attempt to show the animals dragons are afraid of things, too, by demonstrating their aversion to eel. This also fails, as the Monstrous Nightmare who fought in the sheep's pen is spooked when Hiccup accidentally drops the eel, and it slithers toward it. As the Nightmare turns to flee, its tail sideswipes an unfortunate sheep into the opposing wall. The teens try to help the animals get over their fear by showing what the dragons have in common. Fishlegs brings out a week-old Terrible Terror egg, and three chickens appear to calm down upon seeing it, one even jumping on top of it as though it were a normal egg. This gives the trainers a glimmer of hope their effort works, until the egg explosively hatches. By the time the storm arrives, the teens haven't made progress, and Gobber orders them to be herded into the barn.
Unfortunately, snow blocked the path to the barn, the only location left where the animals can be safe being the Great Hall. Much to the Vikings' dismay, the dragons once more frighten the animals, and this time, there isn't a pen to contain them. The animals, terrified, flee into the blizzard. Hiccup mounts Toothless and prepares to take off after the animals. Gobber attempts to stop him, saying his father would kill him if he allowed anything to happen to Hiccup, and tries to get Astrid to stop him, only to discover she's also going to find the animals. Snotlout, Fishlegs, Ruffnut, and Tuffnut mount their dragons as well, and follow shortly after. Once in the blizzard, Toothless rescues a lamb from falling to its death, while the rest of the teens try to catch the other animals. Gobber and Stoick go after the teens, and are quickly mistaken for yaks, due to the silhouettes of the horns on their helmets. Stoick and Gobber tell the trainers they'll have to return to the Great Hall, and they can follow their footprints back. To everyone's dismay, the snow already covered Stoick and Gobber's tracks, and the blizzard left them with little to no visibility. Stranded in the severe weather, the two men notice the teens are already freezing. Gobber and Stoick huddle with the younger vikings between them to conserve as much heat as possible. Toothless observes this and and brings this to the other dragons' attention, and together, they form a circle around the vikings, spreading their wings to block the snow and wind, and breathing small patches of fire onto the ground for warmth. Toothless sees the lamb he rescued earlier, and leaves the circle to try to convince it to join the humans in the center. At first, the lamb is hesitant, toothless gives a nudge encouraging the Lamb but then toothless sneezes scaring the Lamb again Soon, all the other animals, drawn to the warmth, come to the dragons, until all of them are safe.
The dragons hold out in the storm until the next morning, when the weather improves. The group arrives with all the animals, and the other vikings are overjoyed to see the animals are no longer afraid of the dragons, riding on their backs, and curling up under their wings. Hiccup and his friends arrive next, and announce the chickens are laying eggs again, meaning the animals are no longer hindered by fear. The episode ends with toothless having a butterfly on his nose and he sneezes
- Jay Baruchel as Hiccup Horrendous Haddock III
- America Ferrera as Astrid Hofferson
- Nolan North as Stoick the Vast
- Chris Edgerly as Gobber the Belch
- Christopher Mintz-Plasse as Fishlegs Ingerman
- Julie Marcus and T.J. Miller as Ruffnut and Tuffnut Thorston
- Zack Pearlman as Snotlout Jorgenson
- Tom Wilson as Bucket
- Tim Conway as Mulch
- It's hinted by Ruffnut that Tuffnut is afraid of the dark.
- It's possible that the Monsterous Nightmare and Nadder that appear in this episode are Bucket and Mulch's.
- Hiccup and Astrid sit VERY close together twice and both times they scooted away from each other very quickly. First time when they were trapped and Stormfly and Toothless got them out. Second time explaining to the other teens what happened. Only the second time Fishlegs offers that they stay close to each other to keep warm. The first time they moved away quickly once they realized they were touching and hugging. Astrid even made an akward cough.
- The scene when Astrid and Hiccup are "Dragon-boarding" reflects the scene from the film when Hiccup attempts to fly on Toothless for one of the first times next to a snowy mountain.
- Toothless saves the lamb in a similar way he saved Astrid in the film during the final battle against the Red Death.