Terra Incognita (2008)

In Ruth Downie's second mystery featuring Roman-era army doc Gaius Ruso, the sawbones is now stationed on the outskirts of Britain and investigating the ritualistic beheading of a soldier. But is the knife-wielding killer a local — or a comrade?

Lowdown
Downie's attention to day-in-the-life period details, judiciously doled-out twists, and dry British humor make Terra Incognita one hell of a toga party. B+