In the woods to pick mushroom for their mother, Vic, Gilby and Ylvi cross the river they know they're not allowed to. When they are caught into heavy rain, which makes the river grow, they can't cross it anymore. It would be fine for them to wait if they didn't upset a bear in a cave, which is now on their toe. They hide up a tree and Vic has to invent a "flying fox" to get them out of there and back to the village.