There is an unsettling start to the festive season when news breaks that a robber is on the loose, disguised as Santa Claus and accompanied by a vicious elf. Local policeman Len makes it his mission to capture the trouble-making duo and enlists the help of stationmaster Wilf. Before they set off to track down the criminals, they raid Phyllis and Linda's wardrobes for disguises - but end up looking like Cinderella's ugly sisters.