The holidays promised to be boring... All day long, Alice looked after the capricious neighbors' cats, and after the owner returned, she was accused of stealing an antique doll from the mid-19th century. And this is instead of gratitude... Gleb, Lyuska and Dimon did not abandon their friend in trouble. Having decided to investigate the mysterious disappearance of the doll, they very soon learned the story of four sisters: Magda, Zelda, Bertha and Hildegard. What connection existed between the sisters and the missing doll? Will the friends manage to end up in the famous doll room? How to overcome your own jealousy? And how to escape from the killer? The answers to these questions will appear at the very end of summer, but for now everything is just beginning...