One theory about the origins of Doctor Who‘s Ruby Sunday suggests she might be connected to a classic Fifth Doctor (Peter Davison) story. Davison played the Doctor from 1981 to 1984, leaving the role five years before the classic series was canceled. The 2005 reboot offers hour-long, self-contained episodes rather than serialized stories broken into 30-minute episodes, but is still meant to be a continuation of the original series and sometimes makes references to people and events from the past.
“The Devil’s Chord” took the Doctor (Ncuti Gatwa) and new companion Ruby Sunday (Millie Gibson) to 1963 London, and the Doctor Who episode offered multiple Easter eggs that referenced the show’s long history. The story was set in the same time and place as the original series’ debut episode, which was actually addressed by the Doctor in the episode. There were also some more subtle references that fans who have watched every Doctor Who actor may have picked up on. Notably, this includes a detail that hints at a connection between Ruby and the Fifth Doctor.
Doctor Who revealed a clue about Ruby’s origins during a tense scene in which the Maestro (Jinkx Monsoon) was attempting to steal the music from her soul. The Maestro used vines made out of musical notes to tie Ruby to a pole and was trying to find her secret song. However, when the villain heard the Christmas music that played when Ruby was abandoned at the church as a baby, they backed off, saying she was connected to the One Who Waits.
The One Who Waits was previously mentioned by the Toymaster (Neil Patrick Harris) in “The Giggle.” The Toymaker mentioned this character as the only creature he was unable to defeat at a game, but would not give more information. Similarly, the Maestro, who said they were a child of the Toymaker, was so scared of The One Who Waits that they backed off from Ruby and refused to explain further. The only other clue the Maestro gave about The One Who Waits was that he might have been present at the time Ruby was left at the church.
The One Who Waits is likely an immortal being, and one possibility for The One Who Waits’ identity is that he is one of the race of Eternals that was last seen during 1983’s “Enlightenment.” This four-part serial was the third segment of a trilogy involving a new companion who had been tasked by the Black Guardian to kill the Doctor. The Eternals were immortal beings who were stealing humans from various timelines to help them race historical sailing ships through space in an effort to gain enlightenment and eternal wisdom.
At the episode’s conclusion, the Black Guardian was defeated, causing both he and the White Guardian to disappear. The Eternals returned to the void of time and space, and presumably, they’re still there, considering that they can’t die. With that in mind, there’s a chance The One Who Waits is one of these Eternals. That possibility is boosted by their amoral nature, which is entirely in line with what’s known about The One Who Waits.
Additionally, the name The One Who Waits could also be a reference to “Enlightenment.” A subplot involved an Eternal that was attracted to Tegan (Janet Fielding). He wanted to feed on her mind and also found her beautiful, continually flirting with her even though she rebuffed him and even asked to return to the TARDIS prematurely to avoid him. This Eternal was so obsessed with Tegan that he likely would have waited forever for another opportunity to cross paths with her, which could be where he got the moniker The One Who Waits.
Doctor Who explained the Pantheon as immortal, godlike creatures who are so powerful that even the Doctor fears them., and that the Maestro and the Toymaker are both part of this order. The Doctor is far from cowardly, but he ran away from the Maestro and encouraged Ruby to hide because of the Maestro’s power as a member of the Pantheon, which was also responsible for the Doctor’s bi-generation. This type of immense power could only be wielded by immortal beings that are made of energy rather than matter, which is also an appropriate description of the Eternals.
The Maestro also had little fear, yet they were unable to steal Ruby’s musical energy and seemed scared of the idea of The One Who Waits being connected to Ruby’s birth. The most logical explanation for this is that the Maestro is a lower-order member of the Pantheon than The One Who Waits. Additionally, Ruby’s connection to the One Who Waits must give her power she’s unaware of, as learning about it caused the Maestro to back off and leave her alone.
The Eternals can be linked to several other immortals, with The Black and White Guardians being the most famous. They first appeared during Tom Baker’s “Key to Time” saga, which involved the Doctor and Romana (Mary Tamm) collecting the pieces of the Key to Time on the White Guardian’s behalf. The Guardians returned in the “Mawdryn Undead” trilogy but have not been seen since the end of “Enlightenment” when the White Guardian explained that the Black Guardian’s defeat meant he also had to vanish to maintain balance in the universe.
More recently, the Thirteenth Doctor dealt with Zellin and Rakaya, two immortal lovers who enjoyed planting nightmares in people’s brains and otherwise manipulating humans into destructive behavior. Although these villains were characterized as immortals rather than Eternals, their powers suggest they are part of the same race, or at least, part of the Pantheon. Similarly, the Trickster from Sarah Jane Adventures is a member of the Pantheon of Discord, which could be the same Pantheon the Doctor is referring to now. Any of these villains could be linked to the current story through the return of the Eternals.
The new era of Doctor Who has brought back many of the classic series’ popular villains. The Master, Daleks, and Cybermen have made many appearances, and Doctor Who also reimagined and re-created the Toymaker, who last appeared in a William Hartnell episode that is so old that most of the footage no longer exists. Thus, there is no real reason not to bring back the Eternals, who are more recent villains than the Toymaker. In addition, Russel T. Davies said that he was resting the Master for a while, which leaves an opening for some other villains to emerge.
The introduction of the Pantheon opens the door for the Eternals to return, and there have already been many hints that Ruby is related to them somehow. Ruby’s origins suggest she is connected to the Pantheon and is powerful enough to scare the Maestro. It is thus likely that her origin story is a set-up to reintroduce the Eternals in a new, scarier way that fits well with modern Doctor Who.