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".
Matt Smith (actor)
Matthew Robert Smith (born 28 October 1982) is an English actor. He is well known for his roles as the eleventh incarnation of The Doctor in the BBC series "Doctor Who" and His Royal Highness The Prince Philip, Duke of Edinburgh, in the Netflix series "The Crown". Smith initially aspired to be a professional footballer, but spondylolysis forced him out of the sport. After joining the National Youth Theatre and studying Drama and Creative Writing at the University of East Anglia, he became an actor in 2003, performing in plays like "Murder in the Cathedral", "Fresh Kills", "The History Boys", and "On the Shore of the Wide World" in London theatres. Extending his repertoire into West End theatre, he has since performed in the stage adaptation of "Swimming with Sharks" with Christian Slater, followed a year later by a critically acclaimed performance as Henry in "That Face".