During exams, Mirta gets stuck in a simulator. The Winx are sent after her so that the girls can exit through the emergency exit. After coping with several tests, the girls finally find Mirta. She, like a fairy of illusions, manages to open the exit and the girls end up in... the Cloud Tower. It turns out that everything was a set-up. Fortunately, Stella manages to move with the help of the scepter and returns with the Specialists. Together they escape, but in their haste they get lost in the underground corridors. They will have to spend one night in the fresh air. And so, according to the tradition of the Earth, at the costa Myrta tells the mysterious story of some witches. The Winx are shocked - what if this is the Trix's story? But there is no way to be sure of this. Therefore, with their guesses and assumptions, they return to Alfea, where Faragonda finally lets them go on summer vacation.