Michael Gambon stars as Winston Churchill in this dramatization of Churchills life-threatening stroke in the summer of 1953, when he was prime minister for the .\r \r Watch Michael Gambon and Romola Garai in a scene from Churchills Secret, premiering Sunday, September 11, 2016 at 8/7c on MASTERPIECE on PBS.\r \r Premieres Sunday, September 11, 2016 at 8/7c. Michael Gambon, Lindsay Duncan, and Romola Garai lead an all-star cast in Churchills Secret, a one-night .\r \r Airs on Sunday, September 11th at 8 p.m. on PBS 6.\r \r