MASTERPIECE The Marlow Murder Club, Season 3 Episode Three: “Murder in the Dark: Part I" Sunday, September 20, 2026 at 8/7c on PBS When a man is killed at her university reunion, Becks finds herself on the wrong side of an investigation. Was one of her friends responsible, or was someone else inside the house? Shown (L-R): Ryan (Samuel Barnett), Una (Montserrat Lombard), Becks Starling (Cara Horgan), Jessica (Endy McKay) For editorial use only. Courtesy of Courtesy of Monumental Television, UKTV, and MASTERPIECE.

Masterpiece

Murder in the Dark: Part One
The Marlow Murder Club Season 3 on Masterpiece

When a man is killed during her university reunion, Becks finds herself landing on the wrong side of a murder investigation.
Air Date: Sun, Sep 20, 2026 7:00 PM