Raffi and Galen have managed to evade the Watch, but still must travel the world doing their work for the Order. Summoned to perform an exorcism to release a spirit trapped in a farmhouse, they come upon a hanging at a winter fair. One of the prisoners being hanged is a fellow member of their Order. Galen insists on organizing a rescue, even though it means risking their cover and trusting strangers not to reveal their identities or goals.
"Each of these characters is tested, often in situations where they know that doing the right thing might mean a trap or a loss of something they love."
Solon, the keeper they rescue, insists on bringing a fellow prisoner with them. Marco is a thief, sentenced to death for his trade in relics. This offense is as sacrilegious to the Order as it is illegal to the Watch. The travelers begrudgingly bring him along at the insistence of Solon. "He is a rogue and a heretic," Solon says, "but he and I suffered in the same chains. He won't betray me."
Together, these travelers, along with Carys --- a former Watch spy --- and one of the planet's native Sekoi, search for a golden coronet, rumored to be the only thing that can stop the destruction of Anara. But as it becomes increasingly clear that there is a traitor among them, the group's loyalties are tested. Is it one of the newcomers, the broken Solon and the non-believer Marco? Or Galen, whose fanaticism is that of a man possessed? Or Raffi, whose kindness is matched only by his cowardice?
"My people have a saying," the Sekoi tells Carys, whose former associations with the Watch make her suspect. '"Darkness is a stain that will not wash away'... I will be watching."
"So will I, Graycat," she replies. "Because the Sekoi would sell their only sons for a bent button. That's an old saying, too."
Catherine Fisher weaves the themes of faith and loyalty throughout the Relic Master series. Despite a basic conflict of good vs. evil between the Order and the Watch, she does not shy away from the fact that sometimes people do terrible things