Street of the Five Moons — Elizabeth Peters

What did it mean? The note with the hieroglyphs was found in the pocket of a man lying dead in an alley. The only other item of interest was a piece of jewelry, a reproduction of the Charlemagne talisman. It was good, so good that Vicky Bliss thought she was being shown the real jewel. The goldwork was done by a master; the jewels weren't glass but top-quality synthetic stones. What did it mean?

Vicky didn't know ... yet. But on the sunbathed streets and in the moonlit courtyards of Rome, she was going to find out -- if the dangerously exciting young Englishman didn't get in her way... .