In order to save money, unemployed young man Chen Mo rented Room 404 in an old building on the outskirts of the city, but he did not know that this was the "haunted house" where nurse Lin Wan committed suicide five years ago. On the night he checked in, he received a midnight call from nowhere. The cold female voice on the receiver, the shadow of a white dress shaking in the bathroom mirror, and the old-fashioned landline phone that automatically rang, drew him into a strange mystery.
With the landlord's evasive words and the old policeman's suspicious statements, Chen Mo discovered that Lin Wan's "suicide" had another hidden reason. The scene of death that appeared in the mirror and the clue of the "left hand scar" that the undead guided him led him to locate Lin Wan's neighbor Zhang Lei, who had a grudge due to the death of his wife due to illness. When Chen Mo found Zhang Lei to confront him, Lin Wan's ghost appeared again, completing the "trial" that was five years late. But when all the dust settled, in the bathroom of the new residence, the familiar sound of dripping water and the strange smile in the mirror hinted that this "end" might just be the beginning of another one.
