The pair, played by Lesley Manville and Tim McMullan, first appeared in the six-part BBC drama Magpie Murders in 2022, which was followed by Moonflower Murders in 2024.
Both series were based on novels by Anthony Horowitz, who is best known for the hugely successful Alex Rider spy thrillers.
When the Marble Hall Murders series was first confirmed, Horowitz said: "I'm so happy to bring the team back – stars, director, producers, and crew – for a third instalment of what has been a fantastically successful TV series. I have a feeling this could be the best yet."
Meanwhile, executive producer Jill Green added: "Anthony has once again brought his unique and original perspective to the world of murder mystery. Marble Hall Murders completes the trilogy, and the scripts and lead actors are once again at the top of their game."
Star Tim McMullan is hopeful that Marble Hall Murders isn’t Atticus's last adventure. "I don’t know, but I hope not," he told Radio Times. "It’s not my call. That’s an actor’s life."
Read on for everything you need to know about Marble Hall Murders.
Marble Hall Murders release date: When will it air?
The new series will debut on Saturday 26 September on BBC One at 9.35pm and BBC iPlayer.
Marble Hall Murders: Who is starring in the new series?
New cast members include:
Marble Hall Murders: What will happen?
The six part series is based on the third and final novel in Horowitz’s Susan Ryeland series.
The job leads Susan into another murder mystery, concerning the death of a beloved children’s author. However, this time Susan finds that she herself is a suspect.
Meanwhile in the world of the novel, Atticus is visiting Corfu when he becomes embroiled in the murder of Lady Margaret Chalfont (Hodge). He begins to investigate her family with the help of a Greek detective (Varla).
Marble Hall Murders: Is there a trailer?
Yes – the trailer is available to watch now.
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Marble Hall Murders will premiere on Saturday 26 September on BBC One and BBC iPlayer.
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