This film tells the story of a strange family cut off from the rest of the world. The family consists of a pair of parents, eldest son and two daughters, and the family of five live in a big secret house all day long. The three children were isolated by their father from an early age. They could not get in touch with anyone other than their parents and knew almost nothing about the world beyond the high walls. After their father went to work, they studied and played with their mother in the house. All their knowledge is taught by their parents, and their father tells them that the outside world is extremely dangerous, and if the children want to go out, they must wait for the "dog teeth" to fall off. The father was the only one who could drive outside. He had a normal job, bringing back necessities and rewards for his children, and sometimes brought back a female employee in the company, Christian, who was hired to meet the sexual needs of his eldest son. And her several arrivals are quietly changing the family.