The Zarathustra Principle

Axel and Dieter are student friends, united in the philosophy of Nietzsche and the certain knowledge that God is dead. Yet, somewhere in their city is the first Jewish prophet for two millennia, writing down the words of God.

The body of a young woman is dragged from the Rhine. A drunken night turns to tragedy when student caper turns into murder and a Jewish moneylender is dead. The two deaths set off a sequence of events that test their relationships
with family and friends and change their lives forever.

Set in Weimar Germany at the time of the birth of Nazism, this mystery has murder at its heart.
But philosophy as its core.