Lucinda "Lucy" Peterson has poured years into perfecting a croup remedy at Athena's Retreat, the scientific society she calls home. When the formula vanishes just before she can bring it to market, she's certain a rival apothecary is behind it, and her livelihood along with it. Desperate, she turns to Jonathan Thorne, an investigator at Tierney & Co. who takes cases for anyone from the British government to wronged wives.
Thorne is a former prizefighter and disinherited aristocrat turned sober, methodical single father to his daughter Sadie, and about as far from Lucy's warm impulsiveness as a person can get. As his investigation uncovers a widening list of suspects, from a hostile political faction to an old suitor, the case becomes as much a threat to Lucy's found family at Athena's Retreat as it is to her formula.
Part of Everett's "Damsels of Discovery" series, the novel returns to the world and secondary characters of her earlier Victorian-set romances while starting a new central story.