Melancholy, Idaho Territory, 1882. Bordello madam Hennessey Reed learns a reclusive family has been shot dead, bound in pairs, and dumped on the outskirts of town. Were they chosen at random, left as a warning, or, as members of a burgeoning religion, murdered because of their beliefs?

Encouraged by past success as an amateur sleuth, Hennessey barrels headlong into the search for the killer. Unfortunately, a laudanum addiction and penchant for Irish whiskey can be most unhelpful when hunting a murderer. So, too, strained relations with the town marshal, a cagey Pinkerton agent, and an independent wolfhound who follows her nose, but rarely instruction.

Hennessey knows present-day events are often rooted in the past. When the investigation leads her across societal boundaries and county lines, she is pitched against villains ready and willing not only to pay the ultimate price to wreak havoc and exact revenge, but also to kill whomever gets in their way.