The twentieth season of British science fiction television series Doctor Who began on 3 January 1983 with the story Arc of Infinity, and ended 16 March 1983 with The King's Demons. A 20th Anniversary special, The Five Doctors, followed in November 1983.
The White Guardian warns of impending danger and directs the TARDIS to what appears to be an Edwardian sailing yacht, the SS Shadow, but is actually one of a number of spaceships taking part in a race through the solar system, the prize being Enlightenment. The yacht's Captain Striker and his fellow officers are Eternals who feed off the thoughts and emotions of their kidnapped...