The effects of Brainy's handiwork on the episode the holiday debuted in.
Spook-a-Smurf Eve is a holiday created specifically for an episode of the animated series based on the Belgian comics of the same name, The Smurfs. It is somewhat similar to Halloween, which is also the birthday of Jokey Smurf. On this day, Smurfs dress up in scary costumes in order to win Mother Nature's prize for the scariest costume. There is also a party that includes games, roasting smurfmallows around a fire, and listening to ghost stories around nightfall. However, in the episode that the holiday was first featured, Brainy turned every single Smurf that was wearing a costume into a monster.