Nature knows no good or evil. It is solely human purposes that turn plants into remedies or poisons. This truth is experienced by Father Abel, the cellarer of the Benedictine monastery of Amorbach, as he investigates the operations of the Abbey of Seligenstadt on the Main River in 1787. The plants from the famous monastery garden there inspire the fathers to create various means for or against desire, illness, and greed. Monk's pepper suppresses desire, and theriac becomes a miraculous medicine. But then, the creator of that drug is found dead on the garden terrace. In monk's pepper, the monastic seclusion becomes a trap for Abel. His efforts to sort out the abbey's accounts and clarify the death of his fellow brother lead to threatening events. Abel's participation in a snipe hunt organized by the Archbishop of Mainz turns into a fiasco.