The Dark Monk:

The Dark Monk: A Hangman's Daughter Tale By: Oliver Potzsch translated by: Lee Chadeayne
Fiction: Mystery, Historic, E-book
E-Book Count:12
Book Count:19

Review of book one here.  In this book a local priest that found something during church renovations was murdered.   This leads Jakob and Simon on a quest to find out who killed him and why.  The priest's sister, Benedikta also gets  involved in the quest, making Magdalena jealous.   They quickly learn that it has something to do with the Templers.  Meanwhile, there is a plague going around, bandits, and a group of strange monks in town.  Of course all of them are related to each other (except the plague.)