Chief Supterintendent Peter McGarr of the Dublin Police is enjoying a spring evenign when he's called to a murder scene by a neighborhood priest. The victim is a celebrated biographer, brutally killed with a curious religious object. With obstacles continually thwarting his investigation, McGarr slowly pieces together a puzzle involving a clandestine Catholic organization named Opus Dei-God's Work. But as the detective comes ever closer to exposing the forces behind this dangerous group, he encounters a deadly threat that could destroy those he loves.