The children are tired of being sent by their father to April each year and want to turn the tables on this year. With Miss Moons help, the three exchange their bodies with those of zoo animals and want to frighten their father on the visit. But not he looks today for the animals, but his colleague Jasper. He holds the wand in the mouth of the lama for a medical instrument and confiscates it. How are Miss Moon and the kids supposed to turn back now? And who restrains the animals that roam in their bodies?