Nelly Rapp has learned how to deal with monsters and other dangerous beings by being calm, clever and cunning. But will that be enough in a closely fought battle with one of the last abominable snowmen on earth?

Monster agent Nelly is on winter vacation in the mountains when she receives a report of gigantic footprints in the snow at the border between Finland and Sweden. Does this mean that the few snowmen left on earth are on the move, looking for colder places to live? Snowmen, or Yetis as some people call them, are not to be messed with. And the warm winters of late have almost driven them crazy due to a lack of sleep. Nelly is asked to immediately report anything suspicious. For instance, the red-eyed ski rental service manager… doesn’t he seem unusually grumpy and tired? And why does he suddenly rush out of the store to throw snow all over himself? Nelly realizes that she’ll have to tail him on skis to find answers to her questions.