Melchior receives a crucial clue from an old monk. The key to the ominous murders seems to lie in a tragedy involving betrayal, heartbreak and revenge. Keterlyn's secret also comes to light.

Melchior's detective work attracts the attention of the Inquisition. At the same time, there are increasing signs that not only Steffen, but also Melchior and Keterlyn are in danger. Their future together is at stake.