Sarah Gilchrist has no intention of marrying her dull fiancé Miles, the man her family hope will restore her reputation and put an end to her dreams of becoming a doctor. But in this follow-up to The Wages of Sin, when he is arrested for a murder she is sure he didn't commit, she finds herself his reluctant ally. Returning to 19th century Edinburgh's slums, back alleys, and asylums, Sarah discovers the dark past about a family where no one is what they seem, even Miles himself. It also brings her back into the orbit of her professor, Gregory Merchiston—but can he stave off his demons long enough to teach her the skills that will save her life?