During a hike in the mountains, a group of scout girls treat themselves to lunch. Someone, however, takes one of their hard-boiled eggs. It turns out that the culprit is the devil Pipe, who eventually successes in scaring away not only the girls and their teacher, but also several tourists. The hairy Pipe also steals a birthday cake baked by a father for his ten-year-old son called Bi, who moves on a wheelchair. Everyone thinks that this is a weasel's doing. But on the morning TV news, they announce that there have been sightings of a mysterious creature.