The Three Doctors (Doctor Who)

The Three Doctors is the first serial of the tenth season of the British science fiction television series Doctor Who, first broadcast in four weekly parts on BBC1 from 30 December 1972 to 20 January 1973.

In the serial, the solar engineer Omega (Stephen Thorne), the creator of the experiments that allowed the Time Lords to travel in time, seeks revenge on the Time Lords after he was left for dead in a universe made of antimatter. The Time Lords recruit the time travellers the First Doctor (William Hartnell), the Second Doctor (Patrick Troughton), and the Third Doctor (Jon Pertwee) for help when Omega drains power throughout the universe, threatening all of existence.

The serial opened the tenth anniversary year of the series, and features the first three Doctors all appearing in the same serial. This makes it the first Doctor Who story in which an earlier incarnation of the Doctor returns to the show. It was also Hartnell's last appearance as the First Doctor prior to his death in 1975. Omega would later return to the series in the 1983 serial Arc of Infinity, the 2020 episode "The Timeless Children", and the 2025 two-parter "Wish World" / "The Reality War". The story also marks the end of the Doctor's exile to Earth by the Time Lords, ending a plot device begun prior to Pertwee's tenure, from 1969's The War Games.