My real name is Ona Green, but since the day my life turned upside down, I've been called... Ona Kadabra. A heat wave hits Monville, and Ona and the full moon group plan a refreshing bath in the lake. But hey! The lake became a stinking dump, and a very unhappy creature came out of the water. Ona has to hide the monster before it destroys the town, but where? And if that's not enough, a bunch of angry fairies chase after her. Will the children be able to find a magic that will return the monster to her home? Ona Kadabra is a successful series of books that is at the top of the bestseller lists in Spain. This is the third book in the series. He was preceded by the full moon club and a problem with wings.