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text_A: Peter Capaldi portrayed the Twelfth Doctor in the BBC television series Doctor Who.
text_B: The Twelfth Doctor is an incarnation of the Doctor , the protagonist of the BBC science fiction television programme Doctor Who .. the Doctor. The Doctor ( Doctor Who ). BBC. BBC. science fiction television. Science fiction on television. Doctor Who. Doctor Who. He is portrayed by Scottish actor Peter Capaldi .. Peter Capaldi. Peter Capaldi. Within the series ' narrative , the Doctor is a time travelling , humanoid alien from a race known as the Time Lords .. the Doctor. The Doctor ( Doctor Who ). humanoid. humanoid. alien. Extraterrestrial life. Time Lords. Time Lords. When the Doctor is critically injured , he can regenerate his body , and in doing so gain a new physical appearance , and with it a distinct new personality ; this plot mechanism has allowed the Doctor to be portrayed by a series of actors over the decades since the programme 's inception in 1963 .. the Doctor. The Doctor ( Doctor Who ). regenerate. regeneration ( Doctor Who ). Capaldi 's portrayal of the Doctor is a spiky , brusque , contemplative , and pragmatic character who conceals his emotions in the course of making tough and sometimes ruthless decisions .. the Doctor. The Doctor ( Doctor Who ). Capaldi made his first , very brief appearance as the Doctor in the show 's fiftieth anniversary special `` The Day of the Doctor '' -LRB- 2013 -RRB- , as one of the thirteen incarnations of the Doctor who are summoned to save Gallifrey from destruction .. the Doctor. The Doctor ( Doctor Who ). The Day of the Doctor. The Day of the Doctor. Gallifrey. Gallifrey. Capaldi 's first full appearance as the Doctor was at the end of the 2013 Christmas special `` The Time of the Doctor '' .. The Time of the Doctor. The Time of the Doctor. the Doctor. The Doctor ( Doctor Who ). He is accompanied in the eighth and ninth series by companion Clara Oswald -LRB- Jenna Coleman -RRB- .. Clara Oswald. Clara Oswald. eighth. Doctor Who ( series 8 ). ninth. Doctor Who ( series 9 ). companion. Companion ( Doctor Who ). Jenna Coleman. Jenna Coleman. He also appeared in `` For Tonight We Might Die '' , the first episode of the 2016 spin-off series Class .. For Tonight We Might Die. For Tonight We Might Die. Class. Class ( 2016 TV series ). In the tenth series of Doctor Who , he is accompanied by two new companions  : Nardole -LRB- Matt Lucas -RRB- and Bill Potts -LRB- Pearl Mackie -RRB- .. Nardole. Nardole. Bill Potts. Bill Potts ( Doctor Who ). Doctor Who. Doctor Who. tenth series. Doctor Who ( series 10 ). Matt Lucas. Matt Lucas ( comedian ). Pearl Mackie. Pearl Mackie. On 30 January 2017 , Capaldi announced he would be leaving the programme , with the 2017 Christmas episode being his last .
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