Enola Holmes, the younger sister of the famous detective Sherlock Holmes, lives in a country house with her mother until the age of 14. But it is on the girl's birthday that her mother mysteriously disappears. Therefore, the brothers decide to send their sister to a boarding school... Self-willed Enola flees to London to track down her mother. However, he comes across a mysterious case of the abduction of a young marquis and immediately takes up the investigation. What awaits a young girl in a big dangerous city and will she succeed in a new independent life? For children of secondary school age.