Doctor Who Doctor's nature, somewhere between the twelfth and final incarnation. On rare occasions, other actors have stood in for the lead. In "The Five Doctors", Richard Hurndall played the First Doctor due to William Hartnell's death in 1975; 34 years later David Bradley similarly replaced Hartnell in "Twice Upon a Time". In "Time and the Rani", Sylvester McCoy briefly played the Sixth Doctor during the regeneration sequence, carrying on as the Seventh. For more information, see the list of actors who have played the Doctor. In other media, the Doctor has been played by various other actors, including Peter Cushing in
The Doctor (Doctor Who) Within the fictional narrative, the Doctor is a Time Lord from the planet Gallifrey who travels through time and space in a dimensionally transcendental – "bigger on the inside" – time machine: the TARDIS (Time And Relative Dimension(s) In Space) which takes the exterior form of a 1963 police telephone call box, and retains the appearance throughout the programme. The Time Lords have dedicated themselves to overseeing all of time and space without interference. The Doctor chose to leave home by stealing an obsolete TARDIS model as revealed in the 1969 serial "The War Games" and depicted in the 2013