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.

Olivia Denis is a content young wife with a carefree life in late 1930s London. Then her world is shattered with the violent death of her husband, Reggie. The police want to call it a suicide and close the case, but Olivia knows Reggie couldn't possibly have fired the fatal shot. Further mysteries surface surrounding her husband's death. Did the trustworthy Foreign Office employee betray government secrets? Was his murder linked to the death of a German embassy clerk the same night? And who searched their flat?

If one more person gives Rosemary Lillywhite unwanted advice on when to stop mourning the loss of her beloved husband, she fears she will lose control of her sensibilities. All she wants is to be left alone to drown her misery in a glass of gin and tonic, but when Grace Barton knocks on the door of her dead husband’s investigative office, Rosemary faces a choice: come out of hiding, or turn away someone in need of help.

Scotland, 1924: When Lady Poppy Proudfoot travels to the Highlands for a midsummer party, the last thing she and her fellow guests expect is for a body to wash up beside the loch. Despite protests that it could have been an accident, Poppy is convinced it’s murder and decides to dust off her law degree and hunt for clues. But when the police arrive, the grumpy Inspector MacKenzie dismisses her evidence, insisting a crime scene is no place for a Lady. The nerve!

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.

1926 – Christie is a darling of the literary circuit and the most desired guest in London’s glittering social scene. She can often be found at meetings of the Detection Club – where mystery writers come together to share ideas, swap secrets and drink copiously. But then a fellow author's initiation ceremony takes a gruesome turn, and one of the group ends up dead. Now, Agatha is no longer just the creator of great mystery plots – she’s a player in one.

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…

London, 1922. Between gallivanting in his Rolls-Royce and darkening the doorways of London's hotspots, Lord Reginald "Rex" Bankes-Fernsby has almost succeeded in banishing the battlefield nightmares that plague his sleep. Pity he can't say the same about that nagging lack of direction in his life. If only he were like his best friend Freddie—self-assured, suave, and up to his ears in secrets. But when Freddie is murdered, Rex doubts the verdict. Was Freddie really cut down while up to no good, or was he killed in the line of duty?

London, 1941: Miss Jane Treen is at her desk, strong black coffee in hand and fluffy ginger cat by her side, when her top-secret government work is interrupted by an urgent call to Devon. A woman has been found dead in a lake in a place where she shouldn’t have been. Jane needs to gather the clues and find the killer before someone else from the agency gets hurt… Shy and handsome code-breaker Arthur Cilento is bewildered by the arrival of the efficient Miss Treen and her cat Marmaduke.

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.