In February 1915, the Great War is still raging on the Western Front, but in Westminster, at the centre of Hardcastle's bailiwick, a policeman is shot dead. At first, Hardcastle believes the murderer to have been a disturbed burglar. But as enquiries continue, attention focuses on an antiquarian bookseller, a struggling artist, a reporter, officers of the Royal Flying Corps, both in England and in France, and the activities of Isabel Plowman, the wife of one of them and the lover of others.

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…

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...

England, 1925. When a strange young woman is found murdered on the grounds of Unsworth Castle, the duke and his family are astounded at first, but quickly become enraged when the police begin asking all sorts of impertinent questions. And when suspicions dare to fall on one of their own, it is up to Mr. Quayle, Lord Unsworth's exceedingly efficient secretary, to find the true culprit and save the House of Unsworth from scandal and ruin.

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....

August, 1940. On the streets of London, locals watch with growing concern as German fighter planes plague the city’s skyline. But inside the famous Ritz Hotel, the cream of society continues to enjoy all the glamour and comfort that money can buy during wartime - until an anonymous man is discovered with his throat slashed open. Detective Chief Inspector Coburg is called in to investigate, ably assisted by his trusty colleague, Sergeant Lampson.

Three critically acclaimed recordings are joined together in this dazzling Agatha Christie Triple Bill, read by award-winning narrators Alison Larkin and James Warwick, star of the Partners in Crime TV series on Masterpiece Theater.

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.

In "Murder at the Mousetrap," the first Bunburry book, fudge-making and quaffing real ale in the local pub are matched by an undercurrent of passion, jealousy, hatred and murder - laced with a welcome dose of humour. Alfie McAlister has retreated from London to the peace and quiet of the country to recover from a personal tragedy. But an accidental death - which may have been no accident - reveals that the heart of England is far from the tranquil backwater he imagined.

Ian Rutledge returns to his career at Scotland Yard after years fighting in the First World War. Unknown to his colleagues he is still suffering from shell shock, and is burdened with the guilt of having had executed a young soldier on the battlefield for refusing to fight. A jealous colleague has learned of his secret and has managed to have Rutledge assigned to a difficult case which could spell disaster for Rutledge whatever the outcome. A retired officer has been murdered, and Rutledge goes to investigate.

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.

Evelyn Christie has resigned herself to another long, boring weekend at Hessleham Hall, the home of her husband, Tommy's, family. However, it turns out to be anything but dull when his uncle, the Earl of Northmoor, is shockingly murdered! Evelyn must use all of her sleuthing knowledge, gained whilst she was a member of the Police force during the war, to find out who the murderer is before the bungling local police force decide the Earl was bumped off so Tommy could inherit his title.

The epic tale of Harry Clifton's life begins in 1920, with the words "I was told that my father was killed in the war." A dock worker in Bristol, Harry never knew his father, but he learns about life on the docks from his uncle, who expects Harry to join him at the shipyard once he's left school. But then an unexpected gift wins him a scholarship to an exclusive boys' school, and his life will never be the same again. As he enters into adulthood, Harry finally learns how his father really died, but the awful truth only leads him to question, was he even his father?

Detective Sergeant Chris Waters got the call at 05.29 that July morning. This is it, said DCI Reeve, you'll be first there, it's all yours, you're the crime scene manager. Suddenly, after months of waiting and wondering, Waters finds himself in at the deep end, and alone at the scene of a puzzling murder. As the investigation proceeds, the detectives at Kings Lake Central find themselves visiting familiar places and talking to some familiar faces, while old enmities reappear in the incident room. Before this is over, Chris Waters will need to make a career-changing decision.