Mystery is afoot in a monastery in Bavaria in 1666, a popular pilgrimage destination. Monks are experimenting with lightning, relics are missing, and people are dying and disappearing. The local villagers fear magic and sorcery are involved.
On hand to look into the strange happenings are three unusual pilgrims: the hangman's daughter Magdalena, her medic husband Simon, and the hangman, Jakob Kuisl. Unfortunately, during these times suspects are regularly tortured until they confess, so the true culprits are difficult to discover. Moreover, some dangerous people don't like feisty Magdalena and her relatives nosing into their affairs and take measures to stop them.
Heightening the tension, many pilgrims and villagers have fallen ill, and if the medic can't cure the Count's son he's likely to be hanged as well. I enjoyed this book which had plenty of colorful characters and enough twists and turns to keep it interesting.