British Prime Minister Sir Winston Churchill (Sir Michael Gambon) suffers from a stroke in the summer of 1953, which is consequently kept a secret from the rest of the world.British Prime Minister Sir Winston Churchill (Sir Michael Gambon) suffers from a stroke in the summer of 1953, which is consequently kept a secret from the rest of the world.British Prime Minister Sir Winston Churchill (Sir Michael Gambon) suffers from a stroke in the summer of 1953, which is consequently kept a secret from the rest of the world.