Valérie Lehmann investigates in the Catholic stronghold. When the mortal remains of a woman are found in Lake Sihl, time stands still in Einsiedeln. Who was the woman and how did she die? Identification is not possible, but the investigators find clues that lead to the Einsiedeln monastery. Then a second murder occurs. For Lieutenant Valérie Lehmann, a restless search for the perpetrator begins, as a member of the Benedictine order is also in danger.