Six years after giving up the hunt for a serial killer and leaving the police, Rebecca decides to return to service to escape the depression that is eating away at her and keeping her away from her husband and children. Back in the Criminal Department, she investigates a series of murders and is convinced that the killer is the one she had not been able to stop six years ago. She pursues him relentlessly but memory loss disrupts her work. And when one of the victims turns out to be her husband's mistress, she finds herself directly involved: why was she the only one to know where the body of this woman was? Was it the serial killer who killed her...or was it her, during one of these blackouts? How to investigate when you think yourself guilty? Rebecca will have to reconstruct her past piece by piece to discover the terrifying event that triggered her neurosis and may have led her to kill.