Spring, 1918. The Great War is at a crucial stage, the Germans are making one last push into France, and the Allies are struggling to hold them back. Battle lines are shifting, and men, and their machines, are being sent up and down the front to shore up defenses. Major Heathcliff Lennox, and his batman Greggs, are told to report to their new HQ. They set off on a sunlit day to fly the distance, but the enemy is never far away, and disaster strikes. They're sent crashing to the ground behind enemy lines, where life, death, and love await.

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.

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.

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.

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…

Miss Busby helped Major Heathcliff Lennox solve a series of murders at Bloxford in the Cotswolds. Now, she finds herself drawn into a new murder, but this time, it's just her, and she must rely on her sharp mind and sharper wits to catch a Cotswolds killer, along with a handsome police inspector and a reporter who's keen to make her mark.

Late one night, a distraught young man knocks on the door of retired and recently widowed Ally Bright’s remote home on the Cornish coast. But before she can make sense of his confused words, he’s gone—not to be seen again until he’s found the next morning at the foot of the nearby cliffs.

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...

1923. Lottie Sprigg is a lowly maid. But when she's hired by a wealthy heiress, she embarks on a thrilling journey across Europe and beyond. Lottie's expecting exciting exploits and spectacular sights. But she's not expecting murder . . . In Venice, Lottie befriends a famous opera singer after reuniting him with his lost dog. Early the next morning, the singer's corpse is found floating in the Grand Canal.

When Brian Foley is charged with the murder of his next-door neighbour, the fastidious Arthur Cranham, it seems the case against the blustering showman is cut and dried: prints, DNA, CCTV footage - there can't be any doubt. After all - Brian and Arthur have famously been at war for years. But Jack and Sarah are convinced that the police have it wrong. With time running out, can they prove Brian's innocence and find the real killer? Set in the sleepy English village of Cherringham, the detective series brings together an unlikely sleuthing duo: English web designer Sarah and American ex-cop Jack.

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.

Stephen Munro, a demobbed army officer, reconciles himself to taking a job as a footman to make ends meet. Employed at Wintringham Hall, the delightful but decaying Sussex country residence of the elderly Lady Susan Carey, his first task entails welcoming her eccentric guests to a weekend house-party, at which her bombastic nephew—who recognises Stephen from his former life—decides that an after-dinner séance would be more entertaining than bridge. Then Cicely disappears!

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.

Fiona, Sue, and Daisy, three retired ladies who volunteer at the local charity shop, Dogs Need Nice Homes, can’t believe their favorite customer is dead. Eighty-six-year-old Sarah Brown was found murdered in her hallway by her delivery man, a domino clutched in her hand—with a name scratched on it. When another person is found dead with a domino in their hand, and with the police making no progress, the ladies will need to help unmask a serial killer. At least they have Fiona’s scruffy-haired terrier cross to assist them.

London, 1923. Newly minted research assistant Saffron Everleigh is the first woman to hold the position at University College of London. When she attends a dinner party for the school, she expects to engage in conversations about the university's large expedition to the Amazon. What she doesn’t expect is for Mrs. Henry, one of the professors’ wives, to drop to the floor, poisoned by an unknown toxin. Dr. Maxwell, Saffron’s mentor, is the main suspect, and evidence quickly mounts.