The Devil's Sanctuary — Marie Hermanson

When Daniel arrives in Himmelstal -- a private Swiss psychiatric facility -- to visit his twin brother Max, he has no idea what's in store for him. He finds himself unquestioningly accepting Max's plea for help and the brothers swap places in order for Max to take care of some business. All he claims to need is a couple of days in the outside world to settle his debt. But soon Daniel realizes Max isn't coming back, and that the clinic is far from a place of recovery. Struggling to get anyone to believe who he really is, Daniel finds himself trapped in a cruel and highly secretive prison: this is no sanctuary, it's a living nightmare . . .