The Doctor, also known as Doctor Who, is the main character of the long- running BBC science fiction television series Doctor Who. The character is an extraterrestrial Time Lord who travels through time and space in a spaceship called the TARDIS, often accompanied by companions

. Since the show began in 1963, fourteen actors have officially portrayed the Doctor in the lead role, with the current and fifteenth Doctor played by Ncuti Gatwa starting in 2023

. The transition between actors is explained in the series through the concept of regeneration, a biological ability of Time Lords that changes their appearance and personality after a mortal injury

. Here is a summary of the main actors who have played the Doctor on television:

• William Hartnell (First Doctor, 1963-1966)
• Patrick Troughton (Second Doctor, 1966-1969)
• Jon Pertwee (Third Doctor, 1970-1974)
• Tom Baker (Fourth Doctor, 1974-1981)
• Peter Davison (Fifth Doctor, 1981-1984)
• Colin Baker (Sixth Doctor, 1984-1986)
• Sylvester McCoy (Seventh Doctor, 1987-1989)
• Paul McGann (Eighth Doctor, 1996 TV movie)
• Christopher Eccleston (Ninth Doctor, 2005)
• David Tennant (Tenth Doctor, 2005-2010; also Fourteenth Doctor, 2022-2023)
• Matt Smith (Eleventh Doctor, 2010-2013)
• Peter Capaldi (Twelfth Doctor, 2013-2017)
• Jodie Whittaker (Thirteenth Doctor, 2017-2022)
• Ncuti Gatwa (Fifteenth Doctor, 2023-present)

The Doctor is known for being a scientist and adventurer rather than a medical doctor, though the title "Doctor" has never been fully explained on screen. The character has shown medical knowledge and has referenced studying medicine in the past

. In addition to the main television series, many other actors have played the Doctor in spin-offs, audio dramas, stage plays, and other media

. In summary, "The Doctor" refers to a fictional Time Lord character from Doctor Who , portrayed by multiple actors over the decades, with a unique narrative device allowing the character to regenerate and change appearance while maintaining continuity