The Singer from Memphis (The Athenian Mysteries Book 6)

This “witty" mystery set in ancient Greece is “sure to amuse Lindsey Davis and Elizabeth Peters fans" (Booklist, starred review).
 
In this historical murder mystery that “blends humor with fascinating details about the ancient world," Nicolaos, the only private investigator in Athens, discovers that helping a writer with his book research can be very dangerous (Library Journal). Would-be author Herodotus has hired Nico and his priestess wife, Diotima, to accompany him to Egypt to research that ancient country's history. Unfortunately, Egypt happens to be in the throes of a rebellion against its overlords, the Persian Empire.
 
Pirates infest the sea route. Three different armies roam the Egyptian countryside. The river is full of crocodiles. Everywhere Nico turns, there's a secret agent ready to kill him, and possibly worse, he can't find a decent cup of wine anywhere. A simple investigation is about to turn into a dangerous adventure of international espionage, in a novel that is “recommended for lovers of historical mystery and all things ancient Greek (and Egyptian and Persian and Libyan)" (Historical Novel Society).