Himmelstal, idyllically located in the Swiss Alps, is paradise on Earth. Here, wealthy patients can recover from their burnout syndrome. They spend their days by the pool, enjoying the fresh air and the view of the mountains. When Daniel visits his twin brother Max at the rehabilitation clinic, he is so taken by the "Magic Mountain" atmosphere that he unwittingly accepts a fateful offer: Max urgently needs to go to Italy and asks Daniel to secretly stay in the clinic in his place. But in the picturesque Alpine valley, nothing is as it seems, and what begins as a relaxing vacation quickly turns into a nightmarish game of mistaken identity, where good and evil become indistinguishable.