Renowned therapist Clarissa Virtanen is not afraid to look at the darkest side of humanity. Haunted by the death of a young patient, she will do whatever it takes to save the most vulnerable.

But when Ida - angry, damaged and seemingly suicidal - walks into her office, Clarissa may have met her match.

For Ida has secrets. Murderous secrets, which mark her like a bloodstain. Secrets which drive her to kill. And kill again.

Somehow, Clarissa must find the key to unlock her past. So she makes a bargain with Ida - six months to try and stop her taking her own life. But what if she has entered a game more deadly, and more evil, than she could ever imagine.