On the idyllic coast of San Sebastian, Spain, Dublin pathologist Quirke is struggling to relax - despite the beaches, the cafes and his disarmingly lovely wife. So when he glimpses a familiar face in the twilight at the bar Las Arcadas, it's hard, at first, to tell whether his imagination is just running away with him. Could she really be who he thinks she is, and have a connection with a crime that nearly brought ruin to an Irish political dynasty?

Unable to ignore his instincts, Quirke makes a call back home and Detective St John Strafford is soon dispatched to Spain. But he's not the only one on route: as a terrifying hitman hunts down his prey, they are all set for a brutal showdown.