Alla Zvonareva, in order to live at the luxurious dacha of her scientist uncle, agreed to a scientific experiment - a strict banana diet. But at night, severe hunger drove her to the large refrigerator. One day, while making her way to a food source, Alla saw two intruders stealing a valuable painting. There was a commotion. Uncle and other inhabitants of the dacha did not find anything criminal. And everyone decided that the girl, exhausted by her diet, had simply imagined the scene of the theft of the painting. However, something still seemed suspicious to the professor, so he invited detective Andrei Turovsky. Now Allochka needs to restore her good name and immediately find the robbers.