The girls at the boarding school are preparing for their holidays. Evelyne, Marthe and Mrs Fleury, the French governess, set off together in a car. Meanwhile, the Muraköz mine goes bankrupt due to stock market manipulation by Walter Ákos, putting Evelyne and her family in a difficult situation. She finds out who did it and, with her friend, vows revenge against Walter. By posing as his mistress, she manages to prevent Walter from marrying her. Then she thwarts a promising business deal at Walter...