It started in Foggy Bottom, Marshall, Mayor Goodway, Alex, and Chickaletta were visiting Mayor Humdinger for a big "surprise." They took a long walk to get there, they decided to play a game of "I Spy" along the rest of the way. By the time they made it, Mayor Humdinger invites them to his dinosaur ranch. He said it has real dinos, but instead it was a dinosaur statue. The mayor presents them another fake dinosaur which is a robotic dino driven by the Kitten Catastrophe Crew. No one was pleased about the robot, so they all left, so much disappointment for Mayor Humdinger. As the "safari" was over, the Dino Patroller has arrived to pick up Marshall to visit Rex and Taylor Turbot in the Dino Wilds. As the Patroller left, Mayor Humdinger was upset that his kittens wouldn't roar like a dinosaur, he figured they would follow the PAW Patrol to the Dino Wilds, find a dinosaur, and they could teach his kittens how to roar.
As the PAW Patrol was heading to the Dino Wilds, they got a call from Rex and Taylor. They told their friends that they need help to fix Rex's pup-house, which was destroyed by a baby triceratops. Ryder said they're on their way to help. The Dino Patroller drove to the tunnel, pass the waterfall, pass the meadow, and the PAW Patrol made it to the Dino Rescue Center, where Rex and Taylor were waiting. As Ryder, Rocky, and Rex were about to fix the pup-house, the baby triceratops came back. They need to keep the baby busy, while the pup-house is being repaired. Marshall started playing with him by doing a race.
Meanwhile, Mayor Humdinger and his kittens made it to the Dino Wilds. Mayor Humdinger began searching a dinosaur to teach them how to roar. First, he started with the stegosaurus, but no luck. Second, a pterodactyl, and third, two Tyrannosaurus Rex, but still no luck. Until finally, he gave up. And then all of the sudden, a roar came out from a brachiosaurus Mayor Humdinger was sitting on. He fell onto the dino's back and it ran off, and even hits the kittens' robot dinosaur right into the swamp and it began to sink into the bottom. The brachiosaurus ran through the waterfall, leaving the Dino Wilds on the loose.
Back at the Dino Rescue Center, Ryder, Rocky, and Rex had finished fixing his pup-house. And then, Ryder got a call from Taylor Turbot. She told him about a dinosaur stuck and sinking into a swamp. Ryder says they're on their way as he summons the pups to the Dino Tower. Everyone got geared up and ready for action, Ryder told the pups about a dino stuck in the swamp that they have to help it out. He hired Zuma to use his amphibious dino-car to go across the swamp and help get the dino to solid ground, and Rex to help keep the dino calm. As everyone was ready, Ryder, Zuma, and Rex hopped into their vehicles and drove off to save the swampy dino.
As the PAW Patrol made it to the swamp, Ryder asks Rex if he could understand what the dino is saying. Rex said he doesn't understand it since it's only speaking cat. Ryder used his binoculars to get a better look why it's speaking cat, and he discovered the Kitten Catastrophe Crew inside the dinosaur robot. The robot was sinking lower, the kittens needed to get out. Rex hopped into Zuma's car, and Zuma drove onto the swamp towards the robot. Rex used his dino claw as a tow line, while Zuma drag it back to solid ground. As the kittens are saved, everyone was wondering where Mayor Humdinger would be.
For Mayor Humdinger, he was still riding on the brachiosaurus, and it exited the tunnel. It was snowy on Jake's Mountain, the snow was very slippery. The dino was slipping on the snow and it accidentally broke the ski lift. Jake was surprise to see a real dinosaur as he arrived to see what commotion is about. The dinosaur started to slip again, and Jake started to help, but he snowboarded on the dino and landed on the ski lift, and now he's stuck.
Back in the Dino Wilds, the PAW Patrol was about to take the Kitten Catastrophe Crew home on the Dino Patroller, until Ryder got Jake's call about the brachiosaurus on the mountain, giving Mayor Humdinger a ride. Rex feared a dinosaur so big dinosaur could make a lot amount of damage. Ryder was not going to let it happen, he called the rest of the PAW Patrol to get all paws on deck. As the Dino Patroller arrived at the Dino Tower, the rest of the pups got onboard with their dino-vehicles. And off they go to save Adventure Bay from the dino-tastrophe. As they left the Dino Wilds, Ryder asked to be on the lookout for any sized trouble, a brachiosaurus could be almost 90 feet long, so it could cause a lot of trouble.
As the PAW Patrol made to Jake's resort, Jake was happy to see them, but tripped over and was now hanging on the ski lift's cable wire. Rex used his dino-claw to bring him down safely. Now, all that's left is to fix the ski lift, Ryder hired Rubble to straighten the pole, and Rocky to get the motor working again. They both got the ski lift fixed, now the PAW Patrol has to find the brachiosaurus. Luckily, they found some big footprints, they followed them to try and catch up.
Mayor Humdinger was still riding on the brachiosaurus, and it arrived at Farmer Al's farm and started to eat some hay. But, Bettina was mad about it, she caused the dino to run away again, and cause the silo to go off balance. Farmer Al saw the dino running away as the PAW Patrol arrived. As the silo was about to fall, Rubble used his vehicle to catch it and put it back to its spot. The PAW Patrol drove off again to find the dinosaur. The Brachiosaurus was now at the and met some ostriches. They weren't happy to see him, so the dino ran off again.
The brachiosaurus made it to Adventure Bay and caused a very big mess around town. As the PAW Patrol made it, Ryder asked Skye to get Mayor Humdinger off the dinosaur, while the rest go after it. Skye got closer and tried to give Mayor Humdinger a lift with her harness, but she get closer enough, the brachiosaurus was moving too much. Ryder asked Rex to calm the dino down, but Rex couldn't stop him. The dino reached Katie's Pet Parlor and got his head into the store, giving Skye a chance to give Mayor Humdinger a lift. Cali scared the dinosaur, causing Mayor Humdinger to fly off, but Skye caught him on time. The brachiosaurus ran off again, Mayor Humdinger told the PAW Patrol that the dinosaur needed a friend. Ryder came up with an idea, make a fake dinosaur for the brachiosaurus to have.
The brachiosaurus had reached City Hall and began to make friends with the Chickaletta statue. Mayor Humdinger gave some of the people a tour to see the Brachiosaurus. The people took some flash photography in front of it, causing the Brachiosaurus to be scared. He ran up towards the bridge, his weight was too much for it, the bridge is cracking up. Ryder asked Chase to get the cars off the bridge, and Chase used his megaphone to get everyone off. The bridge was about collapse soon, rocky arrived just in time, with the Dino Patroller now looking like a Brachiosaurus, and Rex was doing the roar. Rex got the dino's attention, and he got off the bridge, with damaging it. Now that the Brachiosaurus is stopped, the PAW Patrol started to bring him back to the Dino Wilds.
As the Brachiosaurus was home, he was happy to see his friends again, and he even thank Ryder by licking him. And Ryder said, "Whenever you have a dino-sized problem, just roar for help." Back in Adventure Bay, Mayor Humdinger was replanting Mayor Goodway's tulips. He said the brachiosaurus made the mess that he needed him to help. Then suddenly, the Kitten Catastrophe Crew scared him with his fake robot dinosaur.