1900. Archaeologist Abigail Wilson returns to the Eternal City as a guest speaker for a festival on Classical Rome, although she also hopes the trip will be a well-earned holiday for herself and her husband, private investigator Daniel Wilson. However, the bloody history of the ancient arena seeps into the present with the violent murder of one of Abigail's colleagues and his wife at the Colosseum itself.

Moving from the Forum to the Spanish Steps, Rome is suddenly the backdrop of another investigation for the Museum Detectives who clash with local authorities and a rising mafia influence in a race to uncover the truth.