Rome, 1900. Fifteen years ago, Abigail Wilson joined an archaeological dig at the Colosseum at the start of her career. She returns now to the Eternal City as a guest speaker for a festival on Classical Rome, including the site of legendary gladiator battles. Travelling with Abigail is her husband, Daniel Wilson, a private investigator with whom she has built up a reputation for solving complex cases. The trip is also meant to be a well-earned holiday, but 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 must contend with the local authorities and a shady mafia influence if they are to crack this case.