Private detective Jerome K. Jerome Bloche is hired by his friend Father Arthur, a former boxer turned Catholic priest, to look into a series of blackmail letters extorting money from his parishioners that share one odd detail: the money is to be donated to the church to repair its famous organ! Meanwhile Jerome's girlfriend Babette gets a shocking surprise when her father, whom she believed to have died when she was a child, shows up on her doorstep. Jerome tries to solve the crime while juggling prickly questions about charity, justice, and mercy.