Doctor Who
Thirteen actors have headlined the series as the Doctor. The transition from one actor to another is written into the plot of the show with the concept of regeneration into a new incarnation, a plot device in which a Time Lord "transforms" into a new body when the current one is too badly harmed to heal normally. Each actor's portrayal is unique, but all represent stages in the life of the same character. Together, they form a single lifetime with a single narrative. The time-travelling feature of the plot means that different incarnations of the Doctor occasionally meet. The Doctor is currently portrayed by Jodie Whittaker, who took on the role after Peter Capaldi's exit in the 2017 Christmas special "Twice Upon a Time".
Doctor Who (film)
Among the actors who were invited to audition for the role of the Doctor but declined the opportunity were Christopher Eccleston and Peter Capaldi. Eccleston and Capaldi would go on to play the Ninth and Twelfth incarnations of the Doctor, respectively, in the revived series of "Doctor Who" which began in 2005. Eccleston turned down the offer to audition for the TV Movie because at the time he felt he was not yet an established enough actor and did not want to be associated with a "brand name" so early in his career. Capaldi declined because he felt it was unlikely that he would be given the part.