Many years ago, a brilliant gentleman, medievalist Edmund Stern committed an unmotivated, from the police point of view, brutal murder. And he ended up in Bodmoor - a prison for mentally ill criminals, where until the end of his days he painted countless faces of the devil. But does this mean that Stern has gone crazy? Or is everything much more complicated and scary? Only Maud, the scientist’s eldest daughter, who remained to live in the family estate on the very edge of the disastrous swamps, knows the answer to this question. Maud's soul is tormented by her own demons, and chilling images of the past emerge from the depths of her memory - like a nameless horror hidden in the heart of the swamps.