The detective story set in the early 20th century is full of suspense, twists and emotions. Military trenches are still full of war victims when superintendent Mondl arrives from Vienna in a small Czech town with the task to track down the serial killer of young men and dispel all doubts that the murders are ritual. Suspicion gradually centers on a few person. The detective finds the truth, and opts for justice. But merciless fate soon pays him back.