England. 1923. After a year away at finishing school where she learned etiquette, deportment, and the difference between a fish fork and a salad one, Kitty Worthington is eager to return home. But minutes after she and her brother Ned board the Golden Arrow, the unthinkable happens. A woman with a mysterious connection to her brother is poisoned, and the murderer can only be someone aboard the train. When Scotland Yard hones on Ned as the main suspect, Kitty sets out to investigate.

The Earl of Wrexford possesses a brilliant scientific mind, but boredom and pride lead him to reckless behavior. He does not suffer fools gladly. So when pompous, pious Reverend Josiah Holworthy publicly condemns him for debauchery, Wrexford unsheathes his rapier-sharp wit and strikes back. As their war of words escalates, London's most popular satirical cartoonist, A. J. Quill, skewers them both.

Twenty-six-year-old Beatrice Hyde-Clare is far too shy to investigate the suspicious death of a fellow guest in the Lake District. A spinster who lives on the sufferance of her relatives, she would certainly not presume to search the rooms of her host's son and his friend looking for evidence. Reared in the twin virtues of deference and docility, she would absolutely never think to question the imperious Duke of Kesgrave about anything, let alone how he chose to represent the incident to the local constable. And yet that's exactly what she does.

England, 1920. Eleanor Swift has spent the last few years travelling the world: taking tea in China, tasting alligators in Peru, escaping bandits in Persia and she has just arrived in England after a chaotic 45-day flight from South Africa. Chipstone is about the sleepiest town you could have the misfortune to meet. But then, from the edge of a quarry, through the driving rain, Eleanor is shocked to see a man shot and killed in the distance. Before she can climb down to the spot, the villain is gone and the body has vanished.

Librarian Sylvia Ashe knows nothing about her past, having grown up without a father and a mother who refused to discuss him. When she stumbles upon a diary that suggests she's descended from magicians, she's skeptical. After all, magicians are special, and she's just an ordinary woman who loves books. She seeks answers from a member of the most prominent family of magicians, but she quickly learns that finding the truth won't be easy, especially when he turns out to be as artless as her, and more compelling and dangerous than books.

The young man with the shock of white-blond hair lay spread-eagled on the floor, surrounded by fallen books. His hand reached out to the scattered pages, as though he was trying to tell her something. But who is he? How did he come to be killed in Flora’s ordinary little bookshop? Flora finds out he was staying at the Priory Hotel, and when the gardener suddenly dies in its beautiful grounds only a few days later, she is certain that something untoward is happening in her quiet village by the sea.

Lady Emily Hardcastle is an eccentric widow with a secret past. Florence Armstrong, her maid and confidante, is an expert in martial arts. The year is 1908 and they've just moved from London to the country, hoping for a quiet life. But it is not long before Lady Hardcastle is forced out of her self-imposed retirement. There's a dead body in the woods, and the police are on the wrong scent. Lady Hardcastle makes some enquiries of her own, and it seems she knows a surprising amount about crime investigation...

Newly returned from finishing school, Lady Juliette Thorndike is ready to debut in London society. Due to her years away, she hasn't spent much time with her parents, and sees them only as the flighty, dilettante couple the other nobles love. But when they disappear, she discovers she never really knew them at all. They've been living double lives as government spies-and they're only the latest in a long history of espionage that is the family's legacy.

Edinburgh, 1911: When Maud McIntyre and her lady’s maid, Daisy, form a detective agency, they never dream their first case will take place at a glamorous house in the Scottish Highlands. But when the duchess of Duddingston, concerned that a notorious jewelry thief will target her lavish weekend party, employs Maud to go undercover as a guest to find the culprit, the agency has its first case to solve....

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.

England, 1865: Newspaper columnist Lady Katherine Bascomb finds herself the subject of speculation when her latest article leads to an arrest in the murders plaguing London. The English believe women ought not to write about such vulgar things as crime, and a particularly attractive detective inspector is incensed that she's interfered with his investigation. To escape her sudden notoriety, Katherine heads to the country - only to witness a murder upon her arrival.

As the London Daily Gazette’s popular gossip columnist, she is extremely adept at sneaking into houses, assuming disguises and overseeing a vast network of spies to ensure she stays abreast of the beau monde’s comings and goings. If it sometimes seems as though she was hiding behind the settee during a particularly fierce quarrel between a husband and his wife, it’s most likely because she was hiding behind the settee during their fierce quarrel.

Recently divorced and reluctantly retired, Julia Bird has fled London to enjoy idyllic rural life in the Cotswolds. Determined to have the perfect English garden, her first job is to tear down the old shed, where she unearths much more than she’d bargained for: a body, apparently buried for decades. But who could it be, and who killed them? The police draw a blank, and even the gossip-fest that is the local book club can’t remember anyone going missing in the village.

Following the death of her husband, Lady Darby has taken refuge at her sister's estate, finding solace in her passion for painting. But when one of the house guests is murdered, her brother-in-law asks her to aid the insufferable Sebastian Gage - a fellow guest with some experience as an inquiry agent. While Gage is clearly more competent than she first assumed, Kiera isn't about to let her guard down, as accusations and rumors swirl.

London 1815. Newly widowed Lily Adler is returning to a society that frowns on independent women. At a ball thrown by her oldest friend, Lady Walter, she expects the scandal, gossip, and secrets. What she doesn't expect is the dead body in Lady Walter's garden. Lily overheard the man just minutes before he was shot: young, desperate, and attempting blackmail. But she's willing to leave the matter to the local constables - until Lord Walter bribes the investigating magistrate to drop the case. Stunned, Lily realizes she's the only one with the key to catching the killer.