Doctor Who is a British science-fiction television program that has been broadcast by BBC since 1963. The Doctor is an extraterrestrial being called a Time Lord and depicts his adventures. In a time-travelling spaceship called the TARDIS, the Doctor explores the universe. The exterior of the TARDIS looks like a blue British policebox, which was a familiar sight in Britain when the series premiered in 1963. The Doctor works with various companions to fight foes, save civilisations, and help people in need.
Since William Hartnell's debut, 13 actors have played the role of the Doctor. Jodie Whittaker was the first woman to play this role on TV in 2017. The show's plot includes the idea of regeneration into new incarnations, which allows Time Lords to "transform" into new bodies when their current body is too damaged to heal normally. Although each actor portrays a different character, they all share the same stage in the story. Different Doctors can occasionally cross paths due to the time-travelling aspect of the plot.
