There is something about September that makes reading feel especially inviting. Summer is starting to slip away, evenings are getting a little cooler, and suddenly sitting somewhere comfortable with a book and a hot drink sounds like a very good way to spend a few hours!
Fall is almost here, Halloween is getting closer, and mystery novels start to feel even more at home on the nightstand.
It also happens to be one of the biggest periods of the entire year for new books.
Publishers traditionally save many major releases for fall, and September 2026 is particularly busy. In the UK, September 10th has even been named Super Thursday 2026, the book industry’s busiest annual publication day, with a huge number of new hardcovers arriving at once.
Mystery fans are very well served this September too. We have a new Miss Marple story, the return of Richard Osman’s We Solve Murders team, historical hotels packed with suspicious guests, a Cornish Halloween case, a New Year’s Eve killing and even Agatha Christie herself appearing as a character.
Here are ten new mysteries worth putting on your September 2026 reading list.
Murders in the Marquee by Dana Mentink
Release Date: September 1st
Dana Mentink starts a new historical cozy series in 1905 San Francisco, inside the rather unusual Grand Mallard Marquee hotel.
Saul Niffler is a former jewel thief trying to stay respectable when he sees someone fall from a penthouse window. The problem? There is no body.
Saul should probably concentrate on his new job as the hotel’s “Duck Commandant,” overseeing its famous daily duck parade.
Instead, aspiring Pinkerton detective Kitty Rossi and elevator operator Henry pull him into an investigation involving his missing predecessor, strange events around the hotel and a very unpleasant find in a drain.
It sounds wonderfully odd.
The Silent Appeal by Janice Hallett
Release Date: September 3rd
Fans of The Appeal are heading back to Lower Lockwood and the Fairway Players, where another theater production is going badly wrong, in Janice Hallett’s Silent Appeal.
The group is rehearsing Agatha Christie’s The Hollow, but old arguments, new arrivals and a frightening accident involving the lighting rig are only the beginning.
Someone won’t make it to opening night. Possible troublemakers include Sarah-Jane’s sister, returning after twenty years abroad, shady newcomer Lucas and Issy Beck, who is now out of prison.
Charlotte and Femi must work through emails, messages and police reports to work out who died, who killed them and why the convicted killer refuses to speak.
Murder at the Grand Alpine Hotel by Lucy Foley
Release Date: September 8th
This may be one of September’s biggest treats for classic mystery fans. Lucy Foley has been given the job of bringing Miss Marple back in a new authorized novel, fifty years after Agatha Christie’s final Marple book.
Jane Marple heads to a luxury hotel high in the Swiss Alps, where the guest list includes an actress, a politician, his wife, a doctor, and several people carrying secrets from their past.
Then a guest enters a mountain gondola alive and is found dead at the top. With bad weather cutting everyone off, Miss Marple has a hotel full of motives to study.
The Midnight Guests by Alex Hay
Release Date: September 10th
A grand hotel opening, rich guests, hidden plans, and a body before the night is over. Alex Hay’s The Midnight Guests takes us to the Hotel Artemis in 1920s London, where owner Diana Gold is preparing for the opening night of the city’s most lavish new hotel.
Millionaires, gamblers, film stars and royalty are arriving, but Diana is particularly interested in two powerful guests expected at midnight.
They played a major part in her rise from poverty, and now they want something from her. Diana has plans of her own.
Then a body is found inside the hotel, and everything starts falling apart…
A Midnight Murder by Kate Wells
Release Date: September 14th
Kate Wells gives the Malvern Farm Mysteries a New Year’s Eve setting this time, and Jude Gray barely gets the chance to celebrate.
She is at the local pub with friends and neighbors when attention turns to the wealthy Merebrook family, whose history already includes an old murder.
A marriage proposal causes fresh arguments among the family, but things get considerably worse when midnight arrives. Fireworks fill the sky, and one of the Merebrooks is found dead.
Jude soon learns that this family has been keeping secrets for years, leaving her with plenty of suspects and the uncomfortable feeling that somebody is prepared to kill to keep the past quiet.
We Chase Shadows by Richard Osman
Release Date: September 15th
Amy, Rosie and Steve are back for the second We Solve Murders mystery, We Chase Shadows, from Richard Osman, and this time their case stretches across several countries.
A body is found at sunrise outside a private villa in the Italian hills, along with a threatening note signed by a mystery man.
The team takes on a client who appears strangely keen to avoid involving the police, and the list of suspects soon includes Sweden’s most-wanted criminal, a sharp ex-wife and a business rival.
The investigation moves between Italy, Barcelona, Palm Springs and Steve’s village pub, while the killer always seems to stay one step ahead of them…
Holmes Away from Home by Samantha Larsen
Release Date: September 16th
Sherlock Holmes fans get a new heroine in Althea Adler, daughter of the famous opera singer and thief Irene Adler.
In London in 1911, Althea receives a postcard containing four puzzling words: “Holmes away from home.” She assumes her mother wants her to break into Sherlock Holmes’s safe, but what she finds raises a much bigger question about her own family.
Soon afterward, Althea attends a gathering at Twickenham Towers, where the Earl of Tipon is murdered. She joins forces with William, Marquess of Sheffield, who is secretly carrying out a government assignment.
Both have secrets, and neither is completely sure the other can be trusted.
The Cornish Halloween Murder by Fiona Leitch
Release Date: September 24th
If you want something that feels properly seasonal, Fiona Leitch is taking Jodie Parker into Halloween territory.
A developer has bought the abandoned St Ann’s convent and cottage hospital near Penstowan and plans to turn it into apartments.
Locals are unhappy, but things become much stranger when disturbing handmade dolls are found hidden inside the walls.
Former police officer Jodie soon hears stories about witches, Wiccans, strange voices and the sound of babies crying. Then one of the builders is found dead at the bottom of a staircase.
Jodie and DCI Nathan Withers must decide whether someone is using local legends to hide a very human murder.
The Case of the Christie Honeymoon Murder by Kelly Oliver
Release Date: September 26th
Agatha Christie becomes part of the mystery herself in the fifth Detection Club novel.
Christie has recently married archaeologist Max Mallowan and is preparing for a honeymoon cruise along the Nile following the success of The Seven Dials.
Unfortunately, British intelligence has spotted some curious links inside the novel and takes an interest in its author, and Eliza Baker is asked to travel with Agatha and Max to help clear her friend’s name.
Her attention soon turns to the Hardwicke family, fellow passengers celebrating a birthday. When someone is found dead in a cabin, Eliza and Theo have another murder case to solve as their steamer continues up the Nile.
A Wedding Date with Death by Maeve Haran
Release Date: September 30th
Sadie Sutton returns in the second Campervan Detective Mystery, and what should be a happy wedding at Winching Priory Hotel goes badly wrong when the groom’s father is fatally poisoned.
Benedict Lawrence was a successful local artist, but Sadie quickly finds that he had made plenty of enemies, including the hotel’s rather unfriendly owners and his ex-wife.
A threatening note sent shortly before his death leads Sadie into Benedict’s younger years and a story involving a secret affair, an old feud and a grudge that never went away.
Then she spots someone familiar in an old newspaper photograph, and the case suddenly becomes much more personal.
What Will You Be Reading In September 2026?
One of the nicest things about September 2026’s mystery releases is just how different they are.
If your idea of a perfect mystery involves snowy mountains, expensive hotels and a classic group of suspects, Murder at the Grand Alpine Hotel is an easy choice. If you prefer your mysteries funny and a little unusual, Murders in the Marquee comes complete with a former jewel thief and a daily duck parade.
Historical mystery fans have The Midnight Guests, Holmes Away from Home and The Case of the Christie Honeymoon Murder, while readers who want familiar faces can return to the worlds created by Richard Osman, Janice Hallett, Kate Wells and Fiona Leitch.
And if you are already thinking about Halloween, The Cornish Halloween Murder may be the one to save for a dark September evening.
Basically, September 2026 gives mystery fans plenty of excuses to cancel our plans, make something warm to drink and start working through that reading pile!!
The only hard part might be deciding which one comes first.
