About the Book: The Locked Room
Join Harriet White in 1930’s London for another glorious Sherlock Holmes-inspired mystery, for fans of Nita Prose and Janice Hallett.
After a very close call on the Norfolk Fens, Harriet White is about ready to hang up her deerstalker and settle back into her normal life, working in a bank on Baker Street. Until she discovers a letter in The Times newspaper challenging Sherlock Holmes to prove his status as the world’s greatest detective, by solving an impossible mystery. The letter, signed Professor James Moriarty, advises Holmes that the crime will be committed within the following seven days. There will be no further clues – Holmes himself must deduce which crime is the correct one to investigate.
Dismissing the letter as a prank, Harry goes about her business until news breaks of the theft of valuable jewel collection from a safe in an apparently locked room in a Mayfair townhouse.
Intrigued in spite of her misgivings, Harry dons a disguise and investigates. But as she begins to unpick the puzzle, a body is found. And now, a stranger, and far more deadly mystery begins to unfold around her…
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About the Author: Holly Hepburn
Holly Hepburn writes escapist, swoonsome fiction that sweeps her readers into idyllic locations, from her native Cornwall to the windswept beauty of Orkney. She has turned her hand to cosy crime inspired by Sherlock Holmes himself. Holly lives in leafy Hertfordshire with her adorable partner in crime, Luna the Labrador.
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My Thoughts
Locked-room mysteries are my Kryptonite, so I was already inclined to be generous with The Locked Room. Add in a female sleuth, a Sherlock-adjacent premise, and 1930s London, and I was fully on board before the first page. What I did not expect was how thoroughly this book would delight me—or how quickly I’d be buying the first two installments in the series for pure, unapologetic pleasure.
The Locked Room drops us back into Harriet White’s world after a near-fatal case on the Norfolk Fens. Harriet is ready to retreat to the relative safety of her bank job on Baker Street, until a provocative letter appears in The Times, publicly challenging Sherlock Holmes to solve an “impossible” crime in seven days. When a jewel theft from a supposedly locked Mayfair room hits the headlines, Harriet’s curiosity—and sense of justice—prove impossible to ignore.
I jumped into this series with book three and never felt lost, which is no small feat. Author Holly Hepburn provides just enough grounding to orient new readers while rewarding longtime fans with deeper character beats. I was also intrigued to learn that the premise draws inspiration from a real historical incident, which adds an extra frisson to the cleverness of the setup.
Hepburn’s writing is witty, assured, and inviting, with a light touch that keeps the pages turning. The historical setting feels lived-in rather than performative. I could see the grand townhouses, the quieter streets, and the sharp contrast between wealth and hardship in interwar London. Period details are woven in naturally, never paraded for effect, which makes the world feel solid and breathable.
This particular mystery unfolds around a snowbound manor and delivers one of the most satisfying locked-room puzzles I’ve read in years. False identities, impossible footprints, and a wonderfully human subplot involving Harriet’s mischievous younger brother keep both the tension and the charm dialed high. Hepburn’s prose is richly evocative; the chill of the house, the glow of firelight, and the small rituals of comfort feel almost tangible, even as the tension tightens and the stakes rise.
The twists genuinely surprised me. The romantic thread simmers gently without ever hijacking the mystery. When the final reveal landed, I actually gasped—then immediately flipped back to earlier chapters to admire how skillfully I’d been misdirected.
The Locked Room is clever, cozy without being complacent, and deeply satisfying for puzzle-lovers. If you adore classic detective fiction but crave a fresh perspective, Harriet White deserves a place on your shelf—and very likely, in your reading rotation for a long while to come.
Goes well with: a blazing fire, a generous glass of brandy, and the delicious certainty that you’re about to be very cleverly fooled.
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