"Robbie Rotten poses as a scary snow monster to frighten the LazyTown kids, but they have some tricks up their sleeves. In the end he flees, and failing to read the signs near the frozen lake, falls into the icy waters. In the spirit of the season it's up to Sportacus to rescue Rotten."
Notes
In the opening, the picture of LazyTown is covered in snow to show it's winter, just like "LazyTown's Surprise Santa".
Also in the opening Stephanie addresses the show as "The LazyTown Snow Monster" but the title show on screen is just "Snow Monster"
In Welcome to LazyTown Stephanie states she will be staying in LazyTown for the summer but this is clearly not the case as it is obviously winter in this episode and LazyTown's Surprise Santa.
Bessie Busybody is the only character absent and doesn't appear in this episode.