Miss Dinah Ashmore has a problem: her sister has gone missing, and the constable isn’t taking it seriously. She decides to take matters into her own hands by hiring a Bow Street Runner, not understanding the danger she has put herself in. Nathaniel Calvert, Earl of Hawthorne, is an agent of the Crown. His assignment is to root out a radical group and bring them to justice. When Miss Ashmore mistakes him as a Bow Street Runner and explains her plight, he suspects that the missing sister might be connected to his case.

When Felicity Thurston is caught alone with a man at a ball, she must marry him to avoid a ruined reputation. But what she doesn't know is that he's the brother of the man she loves.  

A murdered opera singer. A duke drenched in her blood. For Bow Street Officer Hugh Marsden, the brutal killing is a straightforward case. Ever since his exile from polite society, the chance to arrest a high and mighty peer of the realm has never presented itself. Hugh won't snub the opportunity now. But Audrey Sinclair, the Duchess of Fournier, is certain her husband is wrongly accused, and she's determined to prove it to the arrogant Bow Street officer, even if she must employ her most peculiar ability—or perhaps curse—to guide her investigation. After all, a duchess can do as she pleases.

The arrival of Thomas Campbell and his elder brother has the small village of Beauford astir. Not only is Thomas tall, dark, and handsome, he is also rumored to be a most notorious rake. Miss Claire Gardner is young, innocent, and completely infuriating. Yet given an opportunity, Thomas can't help teaching the headstrong beauty a lesson in desire.

Madalene Dowding was devastated when her mother died, leaving her all alone. To honor her mother's legacy, she decides to use part of her fortune to open an orphanage. When a teacher at the orphanage goes missing, Madalene takes it upon herself to start looking for her, even if it means taking her deep into the unsavory parts of London.

Much to her father's dismay, Miss Amelia Buxton aspires to become a spinster, just like her eccentric aunt. Growing up with parents who married for every reason but love, she has never seen a joyful marriage. When Amelia requests a summer trip to the legendary waters of Brighton, her father allows her the excursion, but with one requirement: She must return engaged, or agree to the proposal of the man of his choosing.

Lady Ludmilla Windmere is mortified. The spinster extraordinaire has fallen in love with her best friend, and that cannot be. The problem? She hasn't met him. Not once. For they have only ever corresponded by letter. When she sets out to uncover his identity, her world shatters. For Addy turns out to be none other but London's worst rake. Adrian St. Addington is perturbed. The rakehell extraordinaire is developing a marked tendre for a spinster, and that cannot be. The problem? She might be mistaking him for someone he is not. Or, what is worse, know precisely who he is. 

Marianne Edgewood is perfectly capable of running Brindale Castle, if only the task would be left to her. A centuries-old house of stone is solid, unchanging, whereas people are not to be relied upon. It matters little that a stranger inherited the castle. She must simply find a way to stay.

Margaret Easton needs a husband, and she needs one now. Her parents are convinced that only a European will do, but Margaret wants nothing more than to stay in England. The trouble is that there is only one man Margaret can think of, or rather, one she cannot forget, and he wouldn’t do as a husband at all. Then she finds herself in his care unexpectedly, and her hunt becomes even more complicated than she could have ever imagined.

As the eldest son of the Duke of Langford, Nathaniel Gresham sees his arranged marriage to Lady Violet Devere as just another obligation to fulfil – highly suitable, if unexciting. But as Violet sets out to transform herself from dowdy wallflower to dazzling young duchess-to-be, proper Nathaniel sets out to prove he's a match for his new bride's vivacity and daring.

After losing her fiancé to a terrible accident, Miss Katherine Blackmore found contentment as a matchmaker to the members of Society. Working alongside her sisters, they strive to secure the most unlikely people with love matches. Everything is perfect until an infuriating lord steps into her office, turning her world upside down. Edward Simpson, the Marquess of Berkshire, has a problem. His sister needs to marry, and quickly. When he approaches Miss Blackmore to hire her services, he does so poorly and ends up soundly insulting her. Luckily, he fares better with his second attempt.

Jasper Sutton—London’s most dedicated scoundrel—needs a wife, and he needs one quickly. He needs one yesterday, in fact. His requirements are precise: she must be capable of mothering the wild twin daughters who have unexpectedly appeared in his life, and so must possess the patience of a saint and the understanding of an angel. Better still if she is plain and has no expectation of a true marriage. He is not about to reform his ways.

Elena MacKinnon has spent the last seven years training to become a proper English lady. When her childhood friend, Captain Theo Donovan, returns from serving in the Navy, he brings along with him Elena’s humiliation for the ill-advised and ardent love letter she wrote him before his departure, which he ignored entirely. Elena hopes to simultaneously stifle his memory of the letter and make him regret overlooking her, showing him just how fine an English lady she can be. The only problem? She is not English but a proud Scot—and her heart may be more enamored with Theo than ever.

Oliver Dasenby is the most infuriating man Primrose Garland has ever known. He may be her brother's best friend, but he has an atrocious sense of humor. Eight years in the cavalry hasn't taught him solemnity, nor has the unexpected inheritance of a dukedom. But when Oliver inherited his dukedom, it appears that he also inherited a murderer. Oliver might be dreadfully annoying, but Primrose doesn't want him dead. She's going to make certain he survives his inheritance - and the only way to do that is to help him catch the murderer!

When faced with an unwanted marriage, Alice Rosemeyer accepts an invitation to the estate of Larkhall. Determined to earn her future security without a husband, she begins operating as the anonymous Ace of Hearts, writing letters and offering advice on behalf of the men eager to secure a match at the close of the London season. If she can manage to keep her identity secret, her reputation intact, and avoid the arrogant house guest, Mr. Thomas Herring, she might just call herself successful.