Alright, before you start chucking tomatoes at my head, give me a chance to explain. If you had suggested this idea to me a year ago, I would have given you a look of extreme disgust, because who could imagine Matthew Crawley playing the Master? But while he famously played Mr Nice Guy on Downton Abbey, Dan Stevens has a much greater acting range than that. His critically lauded performance in The Heiress on Broadway last year revealed the ability to play a cold, calculating manipulator, something that for me has always defined the Master. I think the contrast between an older, wilier Doctor and a younger, more genteel Master would be an avenue worth exploring.