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 .\rbr\rbrWatch Michael Gambon and Romola Garai in a scene from Churchills Secret, premiering Sunday, September 11, 2016 at 87c on MASTERPIECE on PBS.\rbr\rbrPremieres Sunday, September 11, 2016 at 87c. Michael Gambon, Lindsay Duncan, and Romola Garai lead an all-star cast in Churchills Secret, a one-night .\rbr\rbrAirs on Sunday, September 11th at 8 p.m. on PBS 6.