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".
Ninth Doctor
Christopher Eccleston's casting as the Ninth Doctor was announced on 22 March 2004. He was the production team's first choice for the character. Other actors linked to the role included Bill Nighy, Richard E Grant, Anthony Head, Eddie Izzard, Hugh Grant and Alan Davies. Jane Tranter, BBC Controller of Drama Commissioning, stated in the announcement of his casting that casting an actor of Eccleston's reputation signalled "our intention to take "Doctor Who" into the 21st century, as well as retaining its core traditional values – to be surprising, edgy and eccentric". Executive Producer Russell T Davies remarked that casting Eccleston "raises the bar for all of us". Eccleston cited the quality of the scripts as a reason for joining the cast, stating in an interview on BBC's Breakfast programme that he was "excited" about working with Davies. In the press-pack for the series he states that he had emailed the writer to declare his interest in the role. Eccleston enjoyed having the chance to work on a series aimed at a different demographic than his previous work, noting that "it's aimed at families, so I'm kind of acting for children and I feel very lucky to be able to do that". He felt that being cast by Davies in the series was a "risk" because as an actor he is not known for "charm or comedy" and anticipated a potential backlash due to being built up as "an actor of stature" and the difference between his own interpretation of the character and past doctors.