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.

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.

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.

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.

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.

1929: Miss Clara Vale is a woman ahead of her time. Rather than attending Oxford to bag an eligible Duke (as her mother, Lady Vale, so desperately hoped), she threw herself into a degree in chemistry, with aspirations to become a scientist in her own right. But the world isn't ready for Clara. Unable to land a job in science because she's a woman, she is stuck behind the desk at a dingy London library. Until her estranged Uncle dies suddenly, leaving her his private detective agency, and laboratory, in his will.

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...

Istanbul, 1922. Lady Marigold Grey—former British spy and daring adventuress—sets out for England on a luxury train. But where Marigold goes, trouble follows. When the director of the train is murdered—and false evidence linking her to his death emerges—Marigold suddenly finds herself on the fast-track to becoming a prime suspect.

December 1927. Mystery-writer Marius Quin has one previous bestseller, endless looming mortgage payments, and no idea how to write his next book. When his childhood friend Lady Isabella Montague invites him to an intimate New Year’s Eve party hosted by a narcissistic actor, Marius seizes upon the distraction. With his perpetually glum Basset hound along for the ride, he navigates the snowy lanes to the opulent estate of Everham Hall. As the celebrations begin, fireworks light up the sky, champagne corks pop, and then the host is murdered…

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.