Lady Guinevere Nowlton, known as Gwinnie, possesses a talent for the violin and a heart dedicated to helping women from the stews of London. Though the daughter of a duke, at eight-and-twenty, she considers herself on the shelf. She doesn't think any man in society wants a large-boned woman for a wife who stands eye-to-eye, if not taller than her husband! She long ago tucked away dreams of love as she focused on concerts and her charity work at Mrs. Southerlands House for Unfortunate Women.

Concealing her noble heritage behind the name Sarah Knolls, Gwinnie enjoys the freedom to cross class lines and befriend many people, including Mr. Lewis Martin, a Bow Street agent.

But when she stumbles upon the lifeless body of Mrs. Southerland, the lines between her worlds blur. Who would want to harm Mrs. Southerland?

Gwinnie and Mr. Martin delve into Mrs. Southerlands life to uncover the motive behind her murder. The mystery draws them into a web of secrets and intrigue. As they race to unravel the murder, an undeniable attraction blossoms between them, and though they fight against it, their desires become near impossible to ignore.

Can a dukes daughter and a Bow Street agent defy societys constraints and find a way to happiness amidst the shadow of a murder investigation?

As Lady Cecilia Branstoke convalesces after a severe bout of influenza, an urgent plea for assistance arrives from their friend, Mrs. Montgomery: The Earl of Soothcoor languishes in a goal in Lincolnshire, accused of murder. The victim? Mrs. Montgomery's husband, Malcolm, reported dead over two years ago!

The Branstokes travel to Camden House Sanatorium in Lincolnshire where Mr. Montgomery had secretly been a patient. In society, Camden House Sanatorium had a reputation as one of the most modern and successful sanatoriums, a model for other institutions.

But can a reputation be too perfect?

To investigate, Lady Branstoke registers at Camden House as a patient needing further care to recover from her influenza. Meanwhile, Sir James probes outside connections in pursuit of establishing Soothcoor's innocence and identifying the actual murderer.

As the Branstokes delve into the tangled web surrounding Mr. Montgomery's life and death, the fa?ade of Camden House as the perfect sanatorium cracks, revealing the canker of disintegration beneath the polished exterior.