The Doctor (Doctor Who) Time Lords a fixed number of twelve regenerations, meaning that every Time Lord had a total of thirteen incarnations including the original. The plot of "The Time of the Doctor" involves the Doctor receiving a new cycle of regenerations from the Time Lords before his expected demise, triggering the regeneration into the Twelfth Doctor, played by Peter Capaldi. The origins of the programme were explored in the docudrama "An Adventure in Space and Time" as part of the 50th anniversary celebrations of "Doctor Who", which starred David Bradley as William Hartnell. Although Time Lords resemble humans, their physiology differs in
The Doctor (Doctor Who) "who"). The Master was utilising Latin translation in the same serial, posing as "Mr Magister". The Eighth Doctor's companion Grace briefly refers to him by the alias "Dr. Bowman" in the 1996 "Doctor Who" television movie. In "The Wheel in Space" (1968), his companion Jamie McCrimmon, reading the name on medical equipment, tells the crew of the Wheel that the Doctor's name is "John Smith". The Doctor subsequently adopts this alias numerous times over the course of the programme, sometimes prefixing the title "Doctor" to it. In the audio adventure, "The Sirens of Time", when the Fifth Doctor is asked