When ex-priest Tom Shaman, jaded from years in the LA ghetto, decides on a last-minute trip to Venice, he gets much more than the break he'd been hoping for. A brutal killer is on the loose and Tom finds himself catapulted into a series of ritualistic killings unlike anything Venice has ever seen. Enlisted by the Italian police, Tom teams up with investigator Valentina Morassi to dig deep into the city's darkest history, stretching from an ancient civilisation in 700 BC and the sexual decadence of 18th century Italy to the gritty underworld of modern-day Venice. As Valentina and Tom trace the killings through the centuries, they uncover a deadly secret, a secret that generations have killed to protect: a priceless Etruscan mosaic known as the Gates of Hell.