Rising above the city of Collis is the holy Sanctum. And watching over its spires is Catrin, an orphan girl with unique skills—for she alone can spot the building’s flaws in construction before they turn deadly. But when Catrin witnesses a murderer escaping the scene of his crime, she’s pulled into the web of a dangerous man who will definitely strike again. Assigned to capture the culprit is the mysterious, brilliant, and enigmatic Simon, whose insights into the mind of a killer are frighteningly accurate. As the grisly crimes continue, Catrin finds herself caught between murderer and detective while hiding her own secret—a supernatural sight granted by the moon, destined…