MASTERPIECE The Marlow Murder Club, Season 3 Episode One: "The Queen of Poisons: Part I" Sunday, September 6, 2026 at 8/7c on PBS When the Mayor dies in the middle of a meeting, Judith, Becks and Suzie investigate everyone in the room, uncovering scandals, lies and blackmail, in their mission to find the killer. Shown (L-R): Suzie Harris (Jo Martin), Becks Starling (Cara Horgan), and Judith Potts (Samantha Bond) For editorial use only. Courtesy of Courtesy of Monumental Television, UKTV, and MASTERPIECE.

Masterpiece

The Queen of Poisons: Part One
The Marlow Murder Club Season 3

When the mayor of Marlow suddenly dies during a town council meeting, Judith, Becks and Suzie investigate every single suspect trapped in the room.
Air Date: Sun, Sep 6, 2026 7:00 PM