The investigation into a murder case leads the Munich detectives Ivo Batic and Franz Leitmayr to Dannerberg in the foothills of the Alps. The deceased had most recently worked as an auditor in a nunnery there. However, the God-fearing life only seems tranquil at first glance. Evidence quickly mounts that the monastery's caretaker is involved in the crime. But what is the motive? Were there irregularities in the books that the auditor threatened to uncover? No less irritating are two envoys from Rome who are conducting their own investigations in parallel to Batic and Leitmayr. Are the nuns trying to cover up their own misdeeds? And are there other wondrous secrets lurking behind the monastery walls?