The protagonist is the forensic psychologist Martin Lang, who arrives with his wife Pawla to a spa in the mountains. Far from civilization, they want to relax and try to save their relationship. They are going through a serious partnership crisis, which stems from a deeply hidden trauma, and this stay is an ultimatum for them - either they will overcome their problems, or everyone will go their own way. However, the cycle of routine days is disrupted by the arrival of a mysterious shipment - a package with evidentiary material from the investigation of a tragic case. The sender is Lang's fellow psychologist. He needs help from him in a case known as the "death ride", at the end of which four were dead. Lang is reluctant at first, but gradually succumbs to an unknown force that draws him to the tragic event.