The title character of the world's most successful and longest-running television series skips through time in his TARDIS (Time And Relative Dimensions In Space), time machine, which was designed to take any form but is stuck looking like a blue 1950s British police box. The Doctor, a Time Lord from the planet Gallifrey, has been played by eleven actors since the series' start in 1963. He is currently portrayed by Matt Smith.

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Tom Baker appears as the Doctor in 1975.