which actor plays the titular character in it?
Peter Capaldi
Doctor Who (series 10)
Peter Capaldi reprised his role as the Twelfth Doctor in his third and final series; he left after the 2017 Christmas special, while Pearl Mackie portrays the newest companion Bill Potts, after the departure of Jenna Coleman.
when do the new season of doctor who start On 15 April 2017
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Doctor Who (series 10) [SEP] Casting
Peter Capaldi reprised his role as the Twelfth Doctor in his third and final series; he left after the 2017 Christmas special, while Pearl Mackie portrays the newest companion Bill Potts, after the departure of Jenna Coleman. To avoid leaks while casting the new companion, the production team used the word "Mean Town", an anagram of "Ten Woman"; this is a reference to the fact that Bill is the companion of the tenth series, and was revealed by the casting director Andy Pryor to Radio Times. Mackie made her first appearance in the first episode of the tenth series, and portrays the first openly gay companion.