Thomas sat by a side arm of the river, staring into the still water. The fear of the Black Death lingered. Until today, his fingers had felt no swelling. But what about tomorrow? Or the day after? Or in a week?

1348 - a dark year in European history: The plague breaks out and claims tens of thousands of victims. Many are fleeing to save their bare lives. Among them are two young men, Thomas and David. They do not know each other, meet only once, and yet one ultimately owes his life to the other: Thomas, once a novice in a monastery, initially joins a group of vagabonds who roam the land, robbing and stealing. But this life soon becomes repugnant to him. Then he encounters a procession of flagellants, strange fellows who try to appease God through self-punishment in order to escape the deadly plague. Their destination is Mainz.

Thomas does not yet know that a Jewish boy named David is also heading to Mainz to deliver a manuscript of immeasurable value to the renowned doctor Abraham, which, if applied correctly, could put an end to the Black Death. But the precious document is stolen from him! Are all hopes now lost?.