Doctor Who is the longest running sci-fi show in the world, and a flagship BBC property. First appearing on air in 1963, it follows the adventures of the Doctor, a Time Lord who travels through time and space, fighting alien monsters and saving the universe. Series eleven of Doctor Who hit the screens in October 2018 with Jodie Whittaker as the Doctor - the first female actor to take on the role - and has already seen record viewing figures.