Frances Wynn, the American-born Countess of Harleigh, enjoys more freedom as a widow than she did as a wife. After an obligatory year spent mourning her philandering husband, Reggie, she puts aside her drab black gowns, leaving the countryside and her money-grubbing in-laws behind. With her young daughter in tow, Frances rents a home in Belgravia and prepares to welcome her sister, Lily, arriving from New York - for her first London season.

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.

June 1933. Independent, young Kitty Underhay has been left in charge of her family’s hotel, The Dolphin, on the tranquil English coast. But when several rooms are broken into and searched, including Kitty’s own, she quickly realizes that something out of the ordinary is afoot at the hotel. Soon, rumors are flying in the cozy town that someone is on the hunt for a stolen ruby. A ruby that Kitty’s mother may well have possessed when she herself went missing during the Great War.

Spring, 1905: Free-spirited like the Thoroughbreds she rides across the Kentucky countryside, Stella takes adventure by the reins when she's asked to attend a mysterious wedding in rural England. But once she arrives at the lush Morrington Hall estate, her cold and ambitious father confesses that he won't only give away his best racehorses as gifts - he has also arranged to give away his daughter as bride to the Earl of Atherly's financially strapped son. Stella refuses to be sold off like a prized pony. Yet despite a rough start, there's something intriguing about her groom-to-be.

At the end of her first unsuccessful season out in society, Lady Georgiana has all but given up on attracting a suitable man - until she receives an invitation to a masked Halloween ball at Broxley Manor. Georgie is uncertain why she was invited, until she learns that the royal family intends to marry her off to a foreign prince, one reputed to be mad.

The year is 1920: Flying in the face of convention, legendary American adventuress Beryl Helliwell never fails to surprise and shock. The last thing her adoring public would expect is that she craves some peace and quiet. The humdrum hamlet of Walmsley Parva in the English countryside seems just the ticket. And, honestly, until America comes to its senses and repeals Prohibition, Beryl has no intention of returning stateside and subjecting herself to bathtub gin.

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...

As half of the writing duo behind England’s most infamous crime column, Miss Caroline Hardcastle has quite the scandalous reputation. It may have cost her a fiancé, but she would much rather bring attention to crimes against those ignored by society than worry about what the ton thinks of her.

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....

England, 1925. After years shut away from the world, former detective Lord Edgington of Cranley Hall plans a grand ball to celebrate his seventy-fifth birthday. But when someone starts bumping off members of his scheming family, the old man enlists his teenage grandson to help find the killer, before one of them is next.

Lady Katherine would rather chase clues than suitors. Her reputation as a matchmaker could give her the cover she needs to follow in her detective father's footsteps. If she catches the Pink Ribbon Killer before he strikes again, she'll win her dowry and her independence in the process. One look through the exclusive Northbrooke estate house party doubles her suspect list. With the help of her trusty maid and her precocious pug, Katherine risks it all to unmask the killer. But is winning her freedom worth putting another debutante in mortal danger?

London, 1925. With their band the Dizzy Heights, jazz musicians Ivor ‘Skins’ Maloney and Bartholomew ‘Barty’ Dunn are used to improvising as they play the Charleston for flappers and toffs, but things are about to take a surprising turn.

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.

Left with an estate on the brink of bankruptcy after their father's death, Lady Marigold Fairfax and her brother open a private investigation firm marketed to the elite . . . to spy on the elite. Dubbed The Imposters, Ltd., their anonymous group soon becomes the go-to for the crème of society when they want answers delivered surreptitiously. But the many secrets Marigold learns about her peers pale in comparison to her shock when she and her brother are hired to investigate her best friend's father as a potential traitor.

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.