Ed and Oucho need to find out about radio waves if they want to win Carl Trouser's quiz. So they build Hemang's Davenportanator, a remote control spider that zooms around the London streets, shouting and squirting water, to help them on their mission. It starts off well, but a mix-up with frequency means Major Cake needs to send his frequency testing machine, which ends up a trifle messy! Will Ed and Oucho make the Davenportanator and win the prize they are after?