A rookie British cop (Naomi Ackie, center) befriends a group of elderly amateur sleuths (Celia Imrie, Helen Mirren, Pierce Brosnan and Ben Kingsley) in "The Thursday Murder Club."
Author Richard Osman (center) poses with the actors from the movie adaptation of his book "The Thursday Murder Club": Ben Kingsley, Pierce Brosnan, Helen Mirren and Celia Imrie.
(From left) Ben Kingsley, Helen Mirren and Pierce Brosnan join forces as retirees hoping to solve a murder mystery in "The Thursday Murder Club."

Spoiler alert! This story contains major spoilers for the book and movie adaptation of “Thursday Murder Club.” Proceed with caution, readers.

Your favorite crime-solving senior citizens are hitting the screen.

“The Thursday Murder Club” hits Netflix this week, an adaptation of Richard Osman’s popular cozy mystery series. It stars Helen Mirren, Pierce Brosnan, Ben Kingsley and Celia Imrie as the titular core four. The story follows a group of armchair detectives at senior living village Cooper’s Chase who turn their magnifying glasses inward after a murder close to home.

The movie adaptation will be followed by Osman’s fifth “Thursday Murder Club” novel, “The Impossible Fortune,” out Sept. 30.

At a runtime of about two hours, the movie is largely faithful to the major plot points, though trims many red herrings and sideplots. What’s the same, and what’s different?

Helen Mirren, Pierce Brosnan, Ben Kingsley, Celia Imrie make a charmingly faithful ‘Thursday Murder Club’

The cast in "The Thursday Murder Club" is a delight. Mirren plays retired detective Elizabeth, Imrie the chirpy newcomer and former nurse Joyce, Kingsley as psychiatrist Ibrahim and Brosnan as the former union bigwig Ron.

With quirky, charming humor, these four bring the “Thursday Murder Club” to life. Elizabeth and Joyce make for a delightful black-cat, golden-retriever pair, and Ron and Ibrahim bring about hilarious shenanigans of their own. One loss is Elizabeth’s global-trotting MI6 background and espionage skills, reduced to only a few mentions in the film.

Passports, not drugs, rule in movie’s villain gang

The four are tasked with solving not one, not two, but three murders – Tony Curran (a Cooper’s Chase coowner in the movie, mere lead builder in the book), Ian Ventham (Cooper’s Chase coowner) and mysterious, unmarked bones dug up in the cemetery.

In the book, several of the murders and crimes in “Thursday Murder Club” connect back to a gang of Tony, Jason Ritchie (Ron’s ex-boxer son) and drug dealers Bobby Tanner and Turkish Johnny/Gianni. They’ve all been up to some shady dealings, mostly involving drugs. In the book, Detective Hudson even travels to Cyprus, attempting to track down Gianni in connection to Tony’s murder.

The movie stays a bit closer to home, and it does away with Johnny altogether. The movie's Tony and Bobby Tanner smuggle immigrants into the UK under the guise of better work and pay, only to withhold their passports and trap them into work. Bogdan, Ian's new lead builder and Tony’s murderer, is one of these workers. He confronted Tony to get his passport back so he can visit his sick mother.

But in the book, it’s a carefully planned revenge killing – Bogdan killed both Johnny and Tony for murdering his friend, a taxi driver who witnessed a drug deal gone wrong. He's not arrested for the murder in the book, but is in the movie.

The movie version also changes Jason's role – at one point, he's arrested on suspicion of Ian's murder (a scene that didn’t occur in the book), but it's revealed that his lack of alibi is because he was sleeping with Ian’s wife. And while movie Jason used to help out Tony and Ian with odd jobs, he isn’t wrapped up in the drug business like he is in the book.

Father Mackie's backstory hits the cutting room floor

Loyal Osman readers might be surprised to learn that Father Mackie only has a few on-screen moments in the movie adaptation, and his heartbreaking backstory is largely cut for time.

In the movie, Father Mackie appears as an outraged Cooper’s Chase community member and priest, mostly present at the cemetery protest. He’s quickly dismissed as a suspect by the core four.

But in the book, it's more than piety causing his distress. Father Mackie is not actually a priest, but a doctor who fell in love with one of the nuns at the church in the ‘70s. The nun got pregnant and killed herself after another nun found out about their affair. She was buried in the cemetery, and Father Mackie does not want to see her disturbed by Ian's plan to dig up the cemetery.

He’s not the only side character with a cut backstory – the book’s Gordon and Karen Playfair (a landowner and his daughter) are missing from the adaptation, despite playing a major role in the murder discovery. Cooper’s Chase resident Bernard’s story of burying his wife’s ashes in the cemetery and then committing suicide is also cut. Patrice, PC Donna de Freitas' mother, was also cut from the film.

Killing for love: Ian Ventham’s murderer remains

The movie stays faithful to the book’s shocking end twist: Founding club member and former detective Penny and her husband John are at the center of the murders in both. In an act of vigilante justice, Penny killed a young man who got away with murdering his girlfriend. She buried his body in the cemetery. Now, decades later, it is these unmarked bones the club investigates.

John killed Ian to stop the excavation project before the bones could be discovered and Penny incriminated. But he didn’t realize that Bogdan – in both the movie and the book – would dig them up anyway and flag the Thursday Murder Club, rendering his efforts futile.

Clare Mulroy is USA TODAY’s Books Reporter, where she covers buzzy releases, chats with authors and dives into the culture of reading. Find her on Instagram, subscribe to our weekly Books newsletter or tell her what you’re reading at cmulroy@usatoday.com.

This article originally appeared on USA TODAY: 'Thursday Murder Club' movie made these changes that could surprise fans of the books

Reporting by Clare Mulroy, USA TODAY / USA TODAY

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