Sunday is a day when people hide from themselves. They try to forget what they did on Saturday and pretend that the coming week will be different from the one that passed.

However, the message of the murderer is crystal clear: you are mine.
For Frida Klein, her home was her sanctuary, until the moment it became the scene of a bloody crime. Under the floorboards, the police had discovered the body of the man she had hired to protect her.
However, the main suspect, Dean Reeve, has been dead for seven years.
The killer chooses his next victims and begins to target her close friends. The police are unable to provide answers. With evil creeping in the dark rooms of a sick mind, psychotherapist Frida Klein realizes that she must find the murderer herself before he finds all her loved ones.