The story begins with Benedict Bridgerton falling in love at first sight with a woman, Sophia “Sophie” Beckett, at a masked ball. The two dance all night but she is forced to run away from the ball at midnight, leaving Benedict wondering where she went.
In truth, Sophie is the illegitimate daughter of the Earl of Penwood, who loved her and treated her as his legitimate child, much to the resentment of his wife, Araminta Gunningworth. Once the Earl passed, Araminta treated Sophie like an unpaid house slave. The other maids helped Sophie to sneak out for the ball, but she is caught out by Araminta when she returns, who forces her to leave the house.
The scene jumps forwards two years, where Sophie is now working as a housemaid for the Cavender’s. Benedict is in attendance at this party and catches Phillip Cavender sexually harassing Sophie. Though Benedict does not recognize Sophie, he defends her from Phillip, who fires Sophie. As such, Benedict feels guilty and promises to find Sophie a job with his mother, Violet.
Whilst they travel to his family home, Benedict falls ill and Sophie nurses him to health. He begins to fall in love with her but knows he cannot marry a housemaid. Instead, he offers to take her as a mistress, but she refuses. After providing her a job with his mother as a lady’s maid, Benedict falls deeper in love with her. One day, he sees her playing blind man’s bluff and her masked face makes him realize that she is the girl from the ball. They argue about why she did not tell him, and Sophie leaves her job, thinking he does not want her around.
Meanwhile, Araminta realizes that Sophie is back in town and has her arrested for theft. However, Sophie’s stepsister, Posy, comes to her aid and reveals that the Earl had left a hidden will, providing Sophie with a dowry. Violet threatens to have Araminta arrested for stealing Sophie’s dowry if she reveals Sophie’s illegitimate background to anyone. Benedict and Sophie finally get married and live happily ever after.
