Pettson and Findus find themselves snowed in their house. The little cat is scared that Christmas is ruined, but Pettson promises that they will celebrate "the best Christmas ever".
Old farmer Pettson gets a kitten from his neighbour Mrs Kosonen and calls the cat Viiru. When Viiru starts to talk, the two become inseparable friends.
The old man Petterson is trying to sleep but his cat Findus is keeping him awake, so they both agree that Findus shall have his own house.