Another beautiful day in Adventure Bay, and the PAW Patrol are in the middle of another rescue. Cap'n Turbot has gotten stuck in a storm drain recovering his keys to the Seal Island Lighthouse, and Hailey is on scene to report on the event. After the captain is rescued, nearby, Mayor Humdinger and Harold sulk, while the Ladybird tries to make off with some of Hailey's shiny camera gear, only to be stopped by the Copycat. Soon enough, it is not long before the three baddies meet up, and agree to team up to take revenge on the Mighty Pups.
Retreating back to Humdinger's hideout in Foggy Bottom, Harold has made badges that allow the Copycat's powers to be transferred to the badges, allowing Harold and Ladybird to regain their superpowers. After Mayor Humdinger suggests stealing the meteor that gives the Mighty Pups their powers, Copycat takes lead as he goes with Harold and Ladybird to carry out the theft of the meteor.
However, knowing they need a distraction to lure the Mighty Pups away from the Lookout, Copycat takes the Flounder and places it tethering precariously on the lip of the mouth of the volcano on Volcano Island. Cap'n Turbot, who had just retired to the his quarters on the Flounder to sleep, soon discovers what happened, and calls the PAW Patrol.
When Ryder learns of the captain's predicament, he summons the pups to the Lookout, the meteor is activated, the Lookout transforms, and the PAW Patrol become the Mighty Pups. After briefing the Mighty Pups on the mission, Ryder takes flight as the pups hop into their hover cars and head out towards Volcano Island.
With them gone, Harold and Ladybird move to steal the meteor from the Lookout, but they soon start squabbling over who gets it, causing them to drop it. When it hits the ground, it appears to power down. This results in the Lookout reverting back to its normal appearance from the Mighty Pups transformation due to losing its power source.
At Volcano Island, after the pups arrive, just as Rubble and Skye are about to carry out their orders to move the Flounder down to the shoreline and back into the water. The loss of the meteor causes their Mighty Pup powers to deactivate, which also disables the other pups' Mighty Pup hover cars since their powers had been taken away from them. Ryder acts quickly by having the pups and Cap'n Turbot stand on the bow of the Flounder while he uses his jet pack to lift the stern up using the shift in weight to cause the Flounder to slide over the edge of the volcano's lip, down the summit, through the jungle, and land safely back in the water. Afterwards, with the Mighty Pups unable to use their hover cars to get home to Adventure Bay due to the loss of their powers, Cap'n Turbot offers to give them a ride home on the Flounder in return for helping him.
Back in Adventure Bay, when Copycat discovers what happened with Ladybird and Harold, as they then take off with the meteor, only to argue over who gets to keep it. At one point, they drop the meteor again, causing a piece to chip off, before they start fighting over who gets to keep it, drawing attention from Mayor Goodway and Hailey. Goodway calls Ryder to let him know. When the team returns to the Lookout, they find their worst fears are true, the meteor is gone.
Forced to rely on their regular PAW Patrol vehicles with their Mighty Pup ones out of action without their Mighty Pup powers to run them, the pups and Ryder pursue the villainous trio, but they soon manage to escape. Luckily, Tuck and Ella, who had seen the Ladybird on Hailey's news report, arrive in full Mighty Pup uniform to help out. It is not long before Chase sniffs out the broken off fragment of the meteor, and the pups use it to regain their Mighty Pup powers. Meanwhile, the continued squabbling between Copycat, Harold, and Ladybird leads to the meteor being dropped in the snow, where it powers up again, but soon encases itself in snow and rolls back towards Adventure Bay.
When the pups see it, they work together to bring it to a stop in front of City Hall, where once Marshall melts off the snow to reveal it to everyone, nearby, Ladybird and Harold soon blame each other for what happened, leading to where they end up destroying the badges that granted them their superpowers, leaving Copycat to try and steal the meteor again himself, but is stopped by Tuck and Ella. Frustrated with his defeat, Copycat retreats back to Hailey's van and reverts back to his normal appearance, but still snarls angrily as he glares back at the Mighty Pups for ruining his plans again, while ensuring they never discover his real identity.
As punishment for their actions, Ladybird, Harold, and Mayor Humdinger have to work together to recover the City Hall bell after it fell on Mayor Goodway's tulips earlier thanks to the meteor, but it proves heavier than they expected. Meanwhile, Mayor Goodway commends the pups on another job well done, before the camera pans over to the Lookout, where the PAW Patrol badge glows momentarily, indicating the meteor is back in place for the next time the Mighty Pups are needed again.