Vampire bats have appeared on Katarangra. Tild and Mukr, together with their friends, bats, decided to drive them away, but saw how, dying in the claws of owls, vampires turn into dying little men. The friends realized that there was a mystery and, in order to solve it, they figured out how to revive one of them. The man turned out to be a little elf and told about the long-standing villainy of the witch Haga, who, with the help of a magic ball, turned the elves who had previously lived on Katarangra into flying vampires and drove them away. Haga died, the vampires found out about this and returned to find the ball and break the spell. The friends took the ball out of the hiding place, and it returned the appearance of elves to the vampires.