With a first look at Harriet Walter and Steve Coogan as Margaret Thatcher and Brian Walden, could the Succession star offer the best portrayal yet of the Iron Lady?

It was the interview that many say broke Margaret Thatcher’s grip on government. When the prime minister sat down with the finest political interrogator of his day, Brian Walden, she soon found herself floundering – not a familiar stance for the Iron Lady. On that day in 1989 Walden pressed Lady Thatcher on the recent resignation of her chancellor Nigel Lawson, asking…