Six, Five, and Three are in the Cosy Room putting up Christmas decorations. Meanwhile, Four is in the corridor repairing the thermostat and he tells Zero not to touch anything. Zero, being a baby, ignores Four. They then run out of round decorations, when the alarm sounds.
They leave and Zero jumps into the thermostat controls. They arrive at the control room, which is also decorated, and Agent 20 says that something's up: her Christmas decorations are changing. Five and Six come out to fix the problem.
Only Jasper is on the couch, so they both get launched, and both land on a door. Three notices that it's snowing outside and wants to go outside but Four thinks it's cold enough indoors and goes to check the heating.
At Agent 20's house, she shows Five and Six that the mince tarts are changing too. Meanwhile, Four observes that the gym has flooded and then the water has frozen. Zero slides down the slide and begins sliding on the ice.
Back at Agent 20's house, she informs Five and Six that her father is having trouble with the wrapping paper going out of control. Six suspects a meanie and tells Agent 20 to keep an eye on her dad while he and Five look for the meanie.
Back at the sofa, the three youngest Numberjacks are sliding around the frozen gym, and Four tries to tell them about the problem with the gym, but Six tells him to wait until later and keep a lookout for strange goings-on. The Shape Japer then flies over Five and Six's heads, which makes Four stammer, "Behind you!". However, the Shape Japer keeps pretending to be a Christmas decoration. Eventually, they notice her and the Japer changes some decorations and flies off.
They start up the brain gain machine to turn the decorations back to normal but the brain gain doesn't hit them. Five then imagines the Shape Japer changing the shape of Santa's reindeer's antlers, a chimney (so Santa couldn't come down), or making a cracker really big.
The Numberjacks then notice that the numbers are missing from an Advent calendar and then they and Agent 20 notice the Numbertaker in the backyard but mistake him for a snowman.
When they realise it's the Numbertaker, they become scared. Meanwhile, One and Two are having fun sliding. Agent 20's family tries to eat dinner but the Spooky Spoon arrives and causes the family's spoons to go out of control. The Numbertaker then takes some of their food. Then, the Shape Japer makes things grow and shrink.
An agent then calls attention to One and Two, who are still sliding, and wonders if they're making the brain gain go wobbly. They then decide that if someone slides in a straight line, the brain gain will also go in a straight line.
Three goes down but falls over on the ice and wobbles a bit, however, she eventually manages to slide in a straight line. The brain gain works and then Five and Six go home.
After the recap, the older Numberjacks make it snow in the gym.
This episode provides examples of
- Call-Back: Three, Five and Six decorate the gym using Six's moving mat, from "Slide and Turn".
- Christmas Episode: This episode takes place on Christmas.
- Dreaming of a White Christmas: There is snow around Agent 20's house. For the record, Numberjacks is set in the UK, where snow around Christmas isn't a given, but it's common.
- Exposed to the Elements: Five and Six go out in the snow but, as usual, they aren't wearing clothes.Five: "This snow's a bit cold."
- Failures on Ice:
- Played straight for the three youngest Numberjacks, who wobble around on the ice. Well, they are babies and a toddler.
- Subverted with Three, who has trouble at first, but then slides in a straight line.
- Flat Joy: At the end, when all the Numberjacks except Zero, say, "Have a merry Christmas!" and cheer, Zero simply states, "Hooray.".
- Pun: After making the brain gain straight, Six says that he will fix things "straight" away.
- Santa Claus: Five imagines Santa when she's imagining what could go wrong with Christmas.
- Saving Christmas: The Numberjacks save Christmas for Agent 20 by getting rid of the meanies.
- Speak in Unison: At the end, the Numberjacks all say, "Have a merry Christmas!" except Zero.
