In a holy city where sins and blessings can be revealed through consecrated touch, Csilla - born without a soul - is worthless to the Church that raised her. But when a series of murders corrodes the magic that keeps the city safe, the Church elders see a use for her flaw: she can assassinate their prime suspect, a heretic with divine heritage, without the stain of sin.

The heretic, however, makes a counter-offer: clear his name and catch the real killer, without becoming a target herself, and he'll use his power to get her a soul. When their investigation catches the attention of Ilan, a ruthless Church Inquisitor demoted for his failure to solve the case, he reluctantly offers his help in order to earn back his position. He’ll bring in the murderer— or failing that, Csilla and the heretic. But as the death toll rises and their hunt pits them against the Faith, Csilla will find that salvation comes at the cost of everything she believes in.