Professor Muddles makes Arthur disappear as he investigates a mystery machine.

Ann Teak and Professor Muddles join team captains Keith Fitt and Gail Force for funny clips and questions, but strange things soon start to happen as Professor Muddles investigates a mystery machine from Arthur's lost-and-found box.

Round 1 is a simple clip round with a question for each team. Gail and Professor Muddles are up first. Arthur reveals a dance clip starring Dan Step, but can they remember the picture on Dan Step's basket? Keith and Ann Teak are next. This time it's a clip starring our very own Gail Force at a running race, but can Keith and Ann remember the trophy that Gail was holding? With Round 1 over, Arthur decides to put the trophies back in the lost-and-found box, where he got them. He's amazed at the stuff that people leave lying around, like a rubber duck, a lamb teddy, and a mysterious and complicated-looking machine. Gail and Muddles are fascinated by the device.

Round 2 kicks off with Nana Knickerbocker's Panto Showdown, featuring Nana's cows attempting to make pizzas. The teams each guess how many pizzas will be made. As Arthur tots up the scores, it's neck and neck!

Onto Round 3, the buzzer round, and this gives Muddles an idea - perhaps the mystery machine is a new type of buzzer! Arthur reveals a clip starring Captain Adorable, and Professor Muddles spots the very same mystery machine in the clip. After the first question, he buzzes in to conclude that the machine is a teleporter. Muddles is fascinated and excitedly presses a button, accidentally causing Arthur to disappear and then reappear far away in the jungle. Not to worry, a good host keeps going, and so Arthur carries on with the quiz via telephone. Muddles attempts to bring Arthur back, but instead he makes Arthur appear in the Antarctic surrounded by penguins. Finally, Muddles presses one last button, and at last Arthur reappears, landing right in Keith's lap. Just in time too, as the klaxon goes to sound the end of the quiz.

Arthur dusts the snow off and calculates the final scores to find out who won!