Charlotte is a sound engineer. Her mother is murdered in her house in the countryside. Once there, Charlotte realizes that she doesn’t know much about her mother’s life in the village. The official investigation isn't going anywhere, and the place seems full of secrets. Charlotte decides to take action. She uses her sound equipment to carry out her own investigation. While listening to a recording just made in the house where the murder took place, Charlotte discovers a strange phenomenon : sounds from the past blend in with sounds from the present.