In recent seasons of Doctor Who, fans have been treated to appearances by several former companions. In the lead-up to the 60th anniversary in the Fall of 2023, the BBC has been pulling out all the stops to create as much hype as possible. Classic companions Tegan and Ace have both recently made prominent appearances in the show, and the upcoming specials will feature Catherine Tate returning as Tenth Doctor's companion Donna Noble, along with David Tennant as The Doctor.
Now that Russell T. Davies is back in the TARDIS console room, there's a pretty high chance that other former companions could pop up in the future. It wasn't uncommon in the original Davies era for past companions to show up again, and with David Tennant returning to the show, it seems that anything is possible. With that in mind, which past companions could make a return to the show?
In Doctor Who, it's technically possible for any companion to return to the show. The time and space travel aspects of the show mean that The Doctor could cross paths with former companions at different points in their timeline, whether they are alive or dead in the canon of the show. For example, look at the appearance of River Song on the show. River's first story in the series was the one that showed her death, and although she knew The Doctor, he had no idea who she was.
River showed up in the show even after her death as an echo, clinging both to Clara and The Doctor. There really is a way to circumvent almost any perma-death in the Doctor Who universe, meaning anyone could reappear. Of course, in reality, time is unfortunately linear, meaning that the actors who portrayed some past companions are no longer with us. However, digital effects advancements could be used to create appearances from former stars.
Of all the companions, there is a pretty strong case for the return of River Song. Not only was River a fan-favorite character, but the nature of her story lends itself to sporadic appearances in the show. As the audience, we know that River was adventuring all over time and space when she wasn't with The Doctor, so there is any number of ways she could return to the show.
In terms of fan service, the return of Rose Tyler is also possible. Currently living with the Meta-Crisis Tenth Doctor in a parallel universe, Rose has turned up in the show after her departure before. Notably, these appearances were integral to the DoctorDonna storyline that is being revisited in the upcoming specials. Could there be a secret cameo on the cards for the anniversary shows?
At the end of the most recent run of episodes, there was a scene showing a support group for the previous companions of The Doctor. Previous companion Graham began the group, and the scene showed several former companions meeting for emotional support. Present at the meeting were Tegan, Ace, Graham, Dan, and Yaz, as well as Jo Grant, Kate Stewart, Mel Bush, and Ian Chesterton. This short scene was a beautiful bridge between old and new Who, and perhaps gave a glimpse of actors willing to make further appearances on the show in the future.
Jo Grant (Katy Manning) was a companion to the Third Doctor and left to get married. Her character has met other incarnations of The Doctor in audio adventures, and The Tenth Doctor even went to visit her from afar in the episode "Death of The Doctor." Mel Bush (Bonnie Langford) traveled with the Sixth and Seventh Doctors, while Ian Chesterton (William Russell) was a companion to the First Doctor. Having any of these companions show up in the current show with expanded roles would be a fun way to bridge the old and new series. Sarah Jane Smith's appearance during the Tenth Doctor's run was an iconic and powerful moment for fans, as was the return of Tegan and Ace.
Doctor Who has always been a show in touch with both its past and its potential future. Referencing the past incarnations of The Doctor and those that have traveled in the TARDIS before has been a part of the new Who since its return in 2005. It's a way for fans of the original series to connect the old and new, and evoke memories of their favorite Doctor and companion team. The show has never shied away from having previous incarnations of The Doctor appear in the show either. For Jodie Whittaker's final show, Paul McGann, Colin Baker, Peter Davison, and David Bradley reprised their roles as previous Doctors alongside the guesting companions.
While it's unlikely that an episode with such a stacked guest cast will occur again anytime soon, there are always possibilities available for The Doctor to accidentally cross paths with a previous companion. There doesn't need to be a cataclysmic event for it to happen. When Sarah Jane Smith appeared in the episode "School Reunion," she just happened to be investigating the same unusual events that Ten was. It wasn't a "special" episode event, it was just an alien of the week episode.
Ultimately, there are almost unending ways to bring previous companions into the mix and there are plenty of actors who are clearly still more than happy to make appearances in the landmark sci-fi show. Whether Russell T. Davies will cash in on these appearances beyond the 60th-anniversary specials remains to be seen. Still, the endless iterations of what could be are worth holding onto, and fitting for a show that is all about unknowns and boundless possibilities.