In a mental hospital, Dr. Fisher (Dan Stevens Dan Stevens) visits a female mental patient Ann (Michelle Dockery Michelle Dockery) several times and tries to help. Ann told him about the strange events that had happened in Brenna's beautiful house. In 1921, Ann, a young and simple country girl, came to London to apply for a job as a tutor. Because of the departure of the former tutor, the employer is in urgent need of a new person to take full care of the children of his deceased brother in his country house. Attracted by the handsome and attractive appearance of his male employer, Ann agreed to the job and got up immediately to go. When she worked in the mansion for a while, Ann found that the two children, Miles and Flora, were very cute and cute, and the happy time together made her love the job gradually. However, one strange thing after another, she found that the two children had been entangled by a man and a woman, and their true identities turned out to be the deceased valet and former governess Zesie. And people's indifference to the depravity and education of Miles and Flora finally made Ann decide to take on the responsibility of protecting them. The film is adapted.