The third and final special episode of Doctor Who season 14, "The Power of the Doctor", is made an even better celebration of BBC’s 100th anniversary with one hidden detail. A time (and space) traveling alien from the destroyed planet of Gallifrey, the Doctor has the ability to regenerate into a new physical form when fatally injured. Thus, since the 1960s, various actors of different genders and ethnicities have taken on the role of the Doctor to extend their story on the screen.

"The Power of the Doctor" takes a look back at the show's history through its multiple Doctors and companions, both acknowledging its traditions and signaling a new, upcoming era. Since the series began in 1963, Doctor Who has featured many official renditions of the character of the Doctor, and many more companions as well. For BBC’s centenary celebration, the show called back actors from each decade that the show has been running for to pay homage to its long history and loyal audience.

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The Power Of The Doctors Features A Returning Star From The 1960s

Doctor Who ian chesterton world record

William Russell, who played one of the first companions of the First Doctor, was a series regular from the very early origins of the show in 1963 until 1965. One of the three original companions to the First Doctor, Russell played Ian Chesterton, alongside the second companion, Barbara Wright, who were both teachers to the Doctor’s granddaughter, Susan Foreman, who was the Doctor’s third companion. At the end of the 2022 special episode, Ian Chesterton meets with many of the Doctor’s companions from over the years to reminisce on their stories and experiences with the Doctor. Ian’s only line in the episode, “Did you say ‘she’?” underscores just how far the show has come from its long run of male Doctors since 1963 to its first female Doctor in 2018, and respectfully sends off Jodie Whittaker’s Thirteenth Doctor with a final salute.

The Power Of The Doctor Features A Returning Companion From The 1970s

Katy Manning as Jo Grant in modern and classic Doctor Who

Another early companion of the Doctor joins the meeting of the companions at the end of the special episode to pay homage to the early years of Doctor Who. Jo Jones (aka Jo Grant), portrayed by Katy Manning, was the Third Doctor’s companion on the show, appearing from 1971 to 1973 and then briefly returning to the Doctor Who spinoff show Sarah Jane Adventures in 2010. At the support group meeting of the Doctor's companions through the decades, Jo Jones jokes that they will be there a while to recount all the crazy adventures they shared with the Doctor.

Many 1980s Doctor Who Stars Return In The Power Of The Doctor

Peter Davison as the Fifth Doctor in the Doctor Who centenary special and Adric's badge

The Doctor Who special episode “The Power of the Doctor” features the most returning characters from the 1980s cast by far. The character of Tegan Jovanka, portrayed by Janet Fielding from 1981 to 1984, was a companion to the Fourth and Fifth Doctors, the latter of whom also makes an appearance in the special episode. Peter Davison, who portrayed the Fifth Doctor from 1982 to 1984, returns to the show in the form of an artificial intelligence hologram created by the Doctor that has the ability to take on the form of any incarnation of the Doctor that it chooses. When Tegan Jovanka is forced to find her way out of the Cybermen’s siege, Davison's Fifth Doctor appears to her in AI hologram form in her moment of weakness, reassuring her of her longlasting importance to him and encouraging her to be brave.

Colin Baker, who was the Sixth Doctor from 1984 to 1986, also makes an appearance in the episode as a part of the Doctor’s memory and consciousness. On the brink of death, or as the previous Doctors call it the “edge of existence”, the Thirteenth Doctor comes face to face with her former incarnations, including the First, Fifth, Sixth, Seventh, and Eighth Doctors, who remind her to fight back, or die trying.

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The Seventh Doctor and his companion Ace also share some screen time in “The Power of the Doctor”, paralleling the reunion between the Fifth Doctor and Tegan. The Seventh Doctor played by Sylvester McCoy appears to Ace, his companion during his seventh incarnation, in the form of an AI hologram, giving them a chance to mend things between them and bring closure to the Doctor-companion pair. Both Sylvester McCoy who played the Seventh Doctor and Sophie Aldred who played Ace were series regular from 1987 until 1989, when BBC first canceled the show.

Paul McGann Returns From Doctor Who's 1996 TV Movie

Eighth Doctor standing by stairs in Doctor Who

Paul McGann reprised the role of the Doctor in the 1996 TV movie Doctor Who, which turned out to be a failed attempt to revive the canceled BBC show. Although the show was not relaunched until 2005, nearly a decade later, Paul McGann solidified his place in Doctor Who history as the Eighth Doctor and earned his cameo spot in the 2022 special episode. Together with the First, Fifth Sixth, and Seventh Doctors, Paul McGann’s Eighth Doctor joins the force of previous regenerations to prevent the Thirteenth Doctor from crossing over the “edge of existence” and guide her back to the land of the living.

David Tennant Represents The 2000s In The Power Of The Doctor

Tenth Doctor holding the sonic screwdriver in Doctor Who

David Tennant, who played the Tenth Doctor from 2005 to 2010, makes a brief but powerful appearance in the last scene of the episode as Jodie Whittaker’s Thirteenth Doctor regenerates into David Tennant’s Fourteenth Doctor. Tennant is married to another Doctor Who actor in real life, Georgia Tennant, who plays the Doctor's daughter in Doctor Who season 4, episode 6, “The Doctor’s Daughter.” Additionally, Georgia is the real-life daughter of the Fifth Doctor, Peter Davison, making “The Power of the Doctor” a family reunion on top of a centenary special. With a five-year run as the Tenth Doctor, Tennant represents Doctor Who to the generation of audiences who grew up with the show in the 2000s.

The Power Of The Doctor Features Actors From The 2010s

Doctor Who First Doctor

Both old and new characters make cameos in the episode from the cast in the 2010s. The First Doctor, originally played by William Hartnell in 1963, was reprised by David Bradley in 2017 and returns in the special as one of the Doctor’s former incarnations. Jemma Redgrave’s first appeared in Doctor Who as Kate Stewart in 2012 during Matt Smith’s run as the Eleventh Doctor, continuing on to be a recurring character until 2015. She returns in the special episode as the leader of the United Nations Intelligence taskforce (UNIT), organizing the capture and imprisonment of the Master, one of the Doctor’s nemeses.

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There Are Even Doctor Who Stars Only Introduced In The 2020s

The Doctor and the Fugitive Doctor meet in Doctor Who

Featuring actors from the 1960s to the 2020s, “The Power of the Doctor” comes full circle with its newest returning characters from the current decade. The Fugitive Doctor, played by Jo Martin, is the first non-white portrayal of the Doctor, and is perhaps the most enigmatic incarnation of all the Doctors. It is unknown when exactly the Fugitive Doctor fits into the timeline of the Doctor’s incarnations, but her introduction to the show in 2020 followed by her cameo in the 2022 special episode gives audiences hope that the Time Lord's past on Gallifrey will be further explored in future episodes of Doctor Who.

Next: Every Previous Doctor Who Didn't Appear In The Centenary Special (& Why)