Doctor Who is played by just a single actor
Doctor Who . The transition from one actor to another is written into the plot of the show with the concept of regeneration into a new incarnation -- an idea introduced in 1966 to allow the show to continue after the departure of original lead William Hartnell who was becoming very ill at the time . Each actor 's portrayal differs , but all represent stages in the life of the same character and form a single narrative . Peter Dougan Capaldi ( born 14 April 1958 ) is a Scottish actor , writer and director , best known for playing the twelfth incarnation of the Doctor in the television series Doctor Who . The Doctor (Doctor Who) . Since the show 's inception in 1963 , the character has been portrayed by twelve lead actors .