The actual outdoor snow scenes in this episode were filmed in Røros, Norway, as Gotland (the regular outdoor filming location for the series) had a warm climate at the time, and didn't have the ideal snowy climate they were looking for. To create the illusion that this is set in the same Swedish town, a thick, lathery foam, much like shaving cream, is spread all over the Villa Villekulla exterior in Gotland (look carefully in the shot where Thunder-Karlsson and Bloom approach the entrance from the outside; they step in what is obviously foam), and the snowfall in the closing shot (despite the obvious sunlight) is torn bits of white paper. (See also the next episode, Pippis jul (1969).)