A younger sister cannot wed before an older sister. It's a law of their society, a rule vehemently obeyed by prominent families in the nobility, and it's always been Ella Harrington's buffer. Ella has never been interested in marrying for anything short of love itself. Unfortunately for her, love is a rarity in the marriages of the aristocracy. Fortunately for her, her sister Emily is precisely one year older than her and is the most unpleasant, disagreeable, sulking woman to ever debut in all of England. So Ella may never have to marry at all. A free woman, she enjoys her time on the sidelines and wishes for nothing more. That is, until a tall, dark, and brooding Duke comes to town alongside an old friend of her brother's. Suddenly, Ella finds herself questioning the antiquated marriage order rule as her buffer begins to feel more like a barrier. Not that it matters. The Duke isn't interested in her anyway. Right?

Abandoned by the man she thought loved her, Claire Denham is left with very few options as she faces the prospect of being disgraced for falling pregnant out of wedlock. In fact, she is left with one. Lord Jack Beresford, the younger son of the late Duke of Ashwood, and often considered "the spare" in comparison to his older brother, has long held a torch for the pretty Claire Denham. When fate throws them together, Jack extends a favour to Claire, and she takes it, turning the lives of their families upside down. As they navigate a marriage of convenience, jealousy, betrayal, old lovers, and the fear of being second best all pose dangerous threats to an already shaky relationship ...