The Twelfth Doctor is a medical procedure.
The Twelfth Doctor is an incarnation of the Doctor , the protagonist of the BBC science fiction television programme Doctor Who . Within the series ' narrative , the Doctor is a time travelling , humanoid alien from a race known as the Time Lords . 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 . In the tenth series of Doctor Who , he is accompanied by two new companions : Nardole ( Matt Lucas ) and Bill Potts ( Pearl Mackie ) .