Lesley Manville and Tim McMullan back for one last Masterpiece murder

A murder mystery was never so cozy as it is on PBS Masterpiece. Just look at Magpie Murders and Moonflower Murders, starring Academy Award nominee Lesley Manville. Manville stars in the series as Susan Ryeland, "a book editor who all too often finds herself involved in baffling murders." Now, Susan and the fictional detective Atticus Pünd (Tim McMullan) will be drawn into one last whodunit in Marble Hall Murders, which will answer the question of "who killed Miriam Crace, the most famous children’s author in the world," per a BBC synopsis.

Anthony Horowitz will adapt the script from the final novel in his own Susan Ryeland series. Marble Hall Murders follows Susan as she returns to England, where "she is reluctantly drawn into a new Atticus Pünd mystery, this time written by a new, young writer," according to the synopsis. "'Pünd’s Last Case' is a story set in 1955, in an exotic villa in Corfu—but the identity of a real killer is hidden in the text, and once again Susan is going to find herself in grave danger."

Per the BBC, the third and final season begins filming in March in Dublin, Corfu, and London. Manville and McMullan are set to return in addition to Rebecca Gatward, who will direct. In a statement, Horowitz said, "I’m so happy to bring the team back—stars, director, producers, and crew—for a third installment of what has been a fantastically successful TV series. I have a feeling this could be the best yet."

Speaking of her on-screen relationship with McMullan, Manville previously told Masterpiece that although Pünd is a figment of Susan's imagination, "They have a great thing that’s good for any couple, whether romantic or platonic: They have humor together, and that’s very bonding for them. And she has such respect for his investigative skills, and he’s very encouraging, spending a lot of time urging her to push forward with her own investigating skills. There’s mutual respect and admiration between them," she said. "I mean, it’s a shame, really, that they’re not a real-life couple. But there’s a real charm about them."