Dieselråttor och sjömansmöss.

Siblings Ofelia and Philémon are on their way home to Sweden to celebrate Christmas with their grandmother. When their father’s money is ruined by rats, he offers the children a coin for every tail they bring. But the cunning diesel rats Lucky Closette and Don Calzone have other plans — and Lucky, who is both brave and mischievous, knows exactly how to put an end to the children's rat hunt.