Distinguished British actor Tim McMullan is playing the role of detective Atticus Pünd in the PBS Masterpiece, BritBox U.K. and Eleventh Hour Films series adaptation of “Magpie Murders,” Anthony Horowitz’s international bestseller.

Previously announced actor Timothy Spall had to step away from the production due to a scheduling clash.

The Royal Academy of Dramatic Art trained McMullan’s theater credits include “Anthony and Cleopatra,” “Twelfth Night,” “Man vs Superman,” “Father and Sons” and “The Master and Margarita.” His screen credits include “The Crown” as Robin Woods, Bernard Jenkins in “Brexit” and Sonny in “Patrick Melrose.”

Joining McMullan in the cast is BAFTA-nominated Daniel Mays (“Line Of Duty,” “Rogue One: A Star Wars Story,” “1917”).

“Magpie Murders” revolves around the character Susan Ryeland, played by Oscar-nominee Lesley Manville (“Phantom Thread”), an editor who is given an unfinished manuscript by bestselling mystery writer Alan Conway, featuring Conway’s detective Atticus Pünd – and has little idea it will change her life.

Olivier Award winning actor Conleth Hill (Varys in “Game Of Thrones”), plays Alan Conway. Other cast members joining the series include Pippa Haywood (“Bridgerton”) and Michael Maloney (“The Crown”).

Peter Cattaneo (“The Full Monty”) is directing the six-part series, which is in production.

McMullan said: “I’m absolutely loving doing ‘Magpie Murders.’ Anthony has written such a brilliant and beguiling script, full of wit, suspense and murder. It’s an immense privilege to be asked to bring to life the wonderful and enigmatic Atticus Pünd. He’s such a great character to play, I feel very fortunate indeed. To be working with such a talented cast is a total joy, and to be also working with Peter Cattaneo, of whom I’m a long-time fan, is the cherry on the cake.”

“I’m beyond thrilled to be joining the hugely talented cast of ‘Magpie Murders,’ not least to finally share the screen with the incredible Lesley Manville,” said Mays. “Anthony Horowitz’ scripts are ingenious. Murder, intrigue with plenty of laughs and tears along the way. I couldn’t put them down. With two timeframes to play in and the actors portraying not one but two roles it presented a wonderful opportunity to create a special piece of television.”

Sony Pictures Television will distribute globally.