It's a frosty Christmas morning and Harry can't wait to pick up his chums Norman the Newt and Malcolm the Mole and take them round for a slap up lunch at his mum's. Excited they arrive at Mrs Woodmouse's house licking their lips at the sight of the delicious Christmas pudding that's cooling on the window ledge. But, oh no! The pudding's been pinched by a rat called Pogue and his gang of rogues. So off they set in hot pursuit, following the rats' trail of crumbs down the rats' dark tunnels where Malcolm's talent for seeing in the dark saves their Christmas Day!