A mist of prophecies - Steven Saylor

Rome, 48 BC: as the forces of Julius Caesar and Pompey the Great wage a bloody civil war in the outreaches of the Empire, the city of Rome becomes a hotbed of intrigue, riven by espionage, greedy profiteering and bitter betrayals.

One day as Gordianus the Finder is crossing the marketplace, a beautiful young seeress stumbles towards him, and dies in his arms. Possibly insane, and with no memory of her past, Cassandra - like her Trojan namesake - had been reputed to possess the true gift of prophecy. For such a gift many in Rome would pay handsomely . . . or resort to murder. Cassandra had been the confidante of the rich and powerful, until she fell victim to a vicious killer.

Gordianus begins to investigate, but as he peels away the veils of secrecy that surround Cassandra's life and death, what he finds has deadly implications, involving some of the most powerful women in Rome - not only endangering his own life, but perhaps the future of Rome herself.