"Mounties Pablo and Tyrone are on duty, defending their Snow Fort, as Ski Patrollers Uniqua and Tasha search for someone to save - all to the sounds of Western Swing."
Tyrone is in the backyard wearing a brown mountie hat. He paces back and forth chanting, but is interrupted when he spots the viewer. Tyrone introduces himself as a mountie and begins singing "I'm a Mountie". During the song, Pablo walks over, wearing the same type of hat, and sings along. After the song ends, Tyrone tells Pablo that today, they will defend the World's Largest Snowball inside a Yukon snow fort.
The backyard transforms into the snowy regions of Canada. Uniqua and Tasha check their equipment, and then sing "Ski Patrol to the Rescue" while skiing over snowy hills. Pablo and Tyrone are shown entering a fort made of snow-covered ice blocks. The camera moves to Uniqua and Tasha, who are far from the fort, skiing up and down lumps of snow, wearing blue ski patrol uniforms. Tasha asks Uniqua if she sees anyone who needs help. Uniqua, exhausted, tells her that she does not. Tasha tells Uniqua that she is tired of never saving anyone in need of help. Uniqua tells her that there is someone who needs help: her. Tasha tells Uniqua that she is perfectly fine, but Uniqua fakes a dizziness and falls into the snow. Tasha, catching on, pulls her out of the snow.
Tasha gives Uniqua hot chocolate out of a vacuum flask to warm her up. Tasha tells Uniqua that she does not feel too good, though she is fine, and falls into the snow. The process Tasha followed occurs again, this time with Uniqua pretending to save Tasha. The girls start to giggle uncontrollably, but eventually get back up, reassured that they will find someone to save. The camera moves to Pablo and Tyrone, who open the door to the snow fort. After they enter, they sing "Snowball Duty". Tyrone tells Pablo that they will keep fort invaders and snowball raiders out no matter what.
Tyrone brings Pablo to a small area in the corner featuring three levers. They begin checking the levers that activate booby traps to keep intruders out of the fort. The camera moves to Uniqua and Tasha, who have found the snow fort and are climbing up the stairs, thinking someone inside it may need help. The camera moves back to the mounties. They have completed their check and Pablo has gone to the upstairs segment of the snow fort. He looks out the window and spots Uniqua and Tasha, thinking they are snowball raiders. He alerts Tyrone.
Pablo begins panicking, but Tyrone calms him down and tells him that they are mounties and they will protect the fort. Pablo asks Tyrone how they are going to protect the World's Largest Snowball if the door to the ball's vault is still open. Tyrone attempts to close it, and yells for Pablo's help. Uniqua and Tasha overhear Tyrone yelling "Help!" and thinks that whoever is inside the snow fort is in need of help from ski patrol. They run to the snow fort. Tyrone activates booby trap number one when he catches sight of them, causing the stairs that the ski patrolers are currently climbing up to turn into one flat piece of slippery ice.
They slide back down to the beginning. Uniqua looks in her pack and finds ice suction cups. She hands two to Tasha and begin climbing the ice sheet with the suction cups. They arrive at the top and ring the doorbell. The mounties are scared because they failed to keep out the patrollers. They do not answer the bell, causing Uniqua and Tasha to think that the their lips have frozen together. The girls sing "Who Could It Be?"
The mounties activate booby trap number two, which dumps snowballs on Uniqua and Tasha. The girls do not give up. Uniqua hands Tasha hooks and they begin climbing up the walls to reach the window. The mounties activate booby trap number three, that causes the blocks of snow and ice making up the snow fort to loosen. This happens when Uniqua and Tasha are using the hooks to get up to the fort window, causing them to shriek as the blocks get loose.
The girls fall off the fort. They go through the ideas they have tried, and Uniqua suggests they dig a tunnel from outside the snow fort to inside of it. Tasha agrees to the idea. The two take shovels out of their packs and begin digging. Pablo asks Tyrone how they are going to find out if the "raiders" have left or not. Tyrone tells Pablo to look out the window.
Once at the top, they wonder how to get out of the fort to scout. They end up using a rope ladder to get from the second floor of the snow fort to the snow-covered ground. Meanwhile, Uniqua and Tasha have dug their tunnel, and discover that the fort is empty, since Pablo and Tyrone have already climbed out using a rope. Outside, Pablo and Tyrone spot the hole dug by Uniqua and Tasha. To make sure there is nobody in the fort, Uniqua and Tasha look upstairs to check for anyone else. Pablo and Tyrone, while Uniqua and Tasha were leaving the first floor, have entered the snow fort again. They find the tunnel and realize that someone could of dug it and stolen the snowball.
Uniqua and Tasha find the window Pablo and Tyrone climbed out of and think that someone could of climbed out. They get out of the fort to look for anyone who has climbed out. Meanwhile, Pablo and Tyrone have noticed that nobody is on the snow fort's first floor. Tasha and Uniqua have realized that nobody is outside. They pause halfway down their descent as Pablo and Tyrone go back in the hole Pablo and Tyrone are on the second floor of the snow fort. Back at the rope ladder, Pablo and Tyrone notice Uniqua and Tasha climbing up to the window. When they spot each other, they all scream because they are very scared of each other. The mounties suddenly fall off the ladder and land in a pile of snow.
The two are now struggling to get out. They yell for help. Uniqua and Tasha dash over to them and pull the mounties out of the snow. The ski patrollers give the boys hot chocolate. Uniqua and Tasha ask Pablo and Tyrone what they were doing, and they answer by explaining to the ski patrollers that they are mounties guarding the World's Largest Snowball, and ask them if they would like to view the snowball. Uniqua and Tasha answer yes. They are brought to the large silver vault in which the snowball is kept.
The girls admire the large ball of snow. Uniqua and Tasha's stomachs growl, because ski patrolling has made both of them hungry. Tyrone invites the others over to his house for a snack. The snowy Yukon transforms back into the backyard as the four sing the end song. The cast heads to Tyrone's house for a snack. Uniqua and Tyrone open the previously closed door. Tyrone shouts "Mounties on duty!" as Uniqua yells "Ski patrol to the rescue!"