WMG / Doctor Who S38E5 "Fugitive of the Judoon"

The other 'Doctors' are alternates rather than past/future Doctors.

Possibly in a similar manner to how Scaroth was fractured across his timeline ("City of Death"), at some point something attempted to fracture the Doctor's timeline to create a version of the Doctor who would be willing to take the more ruthless approach, but this created alternates existing in the prime timeline rather than just creating new timelines altogether.

It's complicated, but it's less of a retcon than the idea that the Doctor has had incarnations before the First Doctor; the existence of the War Doctor was enough of a retcon for the Doctor's known timeline.

• That would also explain why Ruth's TARDIS was a police box when the First Doctor's (William Hartnell's) TARDIS didn't become a police box until the first episode.
• Adding on a "Fractured" Doctor; Possibly either a Doctor from the Season 6B Theory, or even a Valeyard type situation?
• Seemingly Jossed by Chris Chibnall.

The Doctor has become a Legacy Character, In-Universe?

What if Ruth's Doctor is actually a different Time Lord all together, but has chosen to take the name of the Doctor as a Homage to the Original Doctor? So, her TARDIS being modeled after a Police Box would be a deliberate Homage on her part, possibly?

• Doubt it, as why would the screwdriver register them both as Doctors? And then she would know why this Doctor can't remember her.

Ruth is an incarnation between 6 and 7 who the Doctor was made to forget because of the Timeless Child.

There's evidence that Ruth is a past incarnation; her console room is similar to most of the classic series ones and Thirteen has no trouble remembering her after they part ways. In addition, her claim that she doesn't need a sonic screwdriver brings to mind the later years of the classic series, as Five, Six and Seven didn't use the sonic after it was written out early in Five's run.

Now, the Six-Seven regeneration is noted for being a case of Dropped a Bridge on Him. What if that's because it was actually a forced regeneration, done so the Doctor wouldn't know he'd had another incarnation between them?

As for why this would've been done, given that the Timeless Child is apparently a huge secret, that would explain going to such lengths: the Time Lords (the most likely perpetrators) wanted to make absolutely certain that the Doctor would never know what they'd discovered while they were Ruth, thus going to the lengths of even topping up the Doctor's regeneration energy so they wouldn't know they'd regenerated once more than they actually had.

• How would that be even possible when Six was actually seen transforming into Seven onscreen? It's not like the case with Eight, who was never shown physically changing into his successor (initially thought by everyone to be Nine), and thus left a narrative gap for Moffat to place the War Doctor between them.
  • Memory wipes and amnesia? The point being that this is the only other regeneration besides 2 to 3, judging by events, where another incarnation could plausibly be slipped in. And hey, this could even be a metatextual explanation for why Sylvester McCoy had to play Six briefly since Colin Baker refused to return for the scene because he'd been fired.
  • In order for this to be true, then the Sixth Doctor's regeneration as seen by the viewers, would have to be fake (either through Time Lord trickery or the scene being shown from the perspective of someone who believed Six turned directly into Seven), since as mentioned, Six was physically shown transforming into Seven. I find this fairly unlikely, since the show is usually objective about showing what actually happens on screen being what truly happened.
• As of "The Timeless Children", most likely [Jossed: She's actually a pre-Hartnell incarnation. The Doctor actually does not have a regeneration limit, and has had many past lives forcibly erased from their memories in order to keep this from them.

Ruth's Doctor and Gat are from an alternate universe.

Whatever the Master did to devastate Gallifrey ripped open the barriers between alternate realities for that world and its people, sucking TARDISes from other dimensions into Thirteen's cosmos. Neither Ruth nor Gat realized this had happened, and continued their already-in-progress pursuit as if nothing was amiss, unaware that Gat's superiors no longer existed in Thirteen's world, if indeed they ever had.

• Jossed: Chibnall confirmed that Ruth is not from an alternative universe, and that she is really an incarnation of the Doctor.

Ruth is the Swordswoman Doctor from the "Rose" novelization

True, she's not bald (right now), but she's definitely tall, black and willing to use weapons.

Ruth is an incarnation between 2 and 3

(To summarize for those not yet aware, there has been a longstanding theory/WMG, which has been used in the Extended Universe, that when the Time Lords captured the Second Doctor at the end of Troughton's run, they didn't send him to Earth right away. Instead they gave him various tasks to perform for them, often under a group mentioned in the Classic series, Gallifrey's Celestial Intervention Agency. How willing the Doctor was and how hard he tried to get out of the job varied between stories and authors. It wasn't until the Doctor either made too much trouble for the CIA, or almost escaped them one too many times, that they eventually forced the Doctor to regenerate into Jon Pertwee and stranded him on Earth, removing not only his memory of time travel, but of everything that had happened since they first caught him. Since Troughton was season six, and Pertwee season seven, this theory became known as "Season 6b".)

Season 6b is going to be made canon and Gat is the Doctor's handler in CIA, this would explain Ruth's line about her job that she did not apply for and cannot leave.

• I was actually going to theorize that she came between 2 and 3 because not only is it the only regeneration where we don't actually see the change, but in existing Canon the Time Lords did mess with the Doctor's mind, erasing his ability to fly the TARDIS, so, it is possible that the Doctor escaped after regenerating and when they recaptured her they erased her memories of Ruth and gave her an extra regeneration to hide Ruth's presence in the Doctor's past.
  • They may not even have had to give the Doctor an extra regeneration. The Time Lords only said they were going to change the Doctor's appearance, not that they were forcing him to Regenerate. Of course the term hadn't been invented yet, but in-universe it gives us a nice out!
• It may also explain why Ruth's TARDIS has the Classic Control Room, and Police Box exterior, too, since that is the TARDIS look used up until the Middle of the Third Doctor's Era.
• A few other points of note; she does not recognise the Sonic Screwdriver, which puts her before the Third Doctor, the first incarnation to use it, and her TARDIS being a Police Box has to put her after the First. She also specifically calls the TARDIS a "ship", which is something more associated with the early incarnations. Finally, Gat responds to the idea of a multi-incarnation event as an "abomination", which suggests at that point in her timeline, Gallifrey has yet to start plucking past incarnations of the Doctor out of time and forcing them to work together, as often happened in the classic series, and started with the Third Doctor.
  • The Second Doctor had the sonic screwdriver, it first appeared in Fury from the Deep
    • At the time it appears to have only been used as a screwdriver; the Doctor had not yet begun modifying and expanding its uses. The modern sonic probably looks as much like a regular sonic screwdriver as a Swiss army knife does a bread knife, or a cell phone does a 1950s land line phone. Ruth hasn't seen Thirteen use the sonic on any screws, so she'd have no reason to connect it to the simple tool the Second Doctor had until Thirteen names it, and even then she looks skeptical.
    • While the Second Doctor had a sonic screwdriver, not all of the later ones used one. Five didn't bother to replace his after "The Visitation" and neither Six or Seven used one despite the fact it's fairly easy for a Time Lord to make one. Also Ruth knows what a sonic screwdriver is so perhaps she just didn't recognise Thirteen's self-made one.
• As of "The Timeless Children", probably Jossed: She's actually a pre-Hartnell incarnation. The Doctor actually does not have a regeneration limit, and has had many past lives forcibly erased from their memories in order to keep this from them.

The Doctor is The Timeless Child

In "Spyfall", the Master told the Doctor that everything she knew was a lie. What if that didn’t just mean Gallifreyan history but also her own life? If Ruth truly is a past incarnation, then the Time Lords erased all memories of her past before she was the First Doctor.

• Confirmed.

The Meta-Crisis Doctor

The forgotten Doctor necessities a change to the stated fact that the current regeneration cycle is the Doctors first set they will reveal that the Meta-Crisis regeneration doesn't count. This would also remove the honestly bad look of 10 wasting a regeneration on pure vanity.

• The Doctor didn't waste that regeneration — he was dying before he regenerated, and he was alive and well afterwards, exactly what a regeneration is supposed to do, except that he forced the regeneration to only heal him in his current form, and not change his body into a new one. (Side-WMG: If they could find a way to fine-tune this so that the extra Regeneration Energy wasn't lost to the Time Lord in question, then a Time Lord might be able to regenerate many more times than the normal limit of twelve!)
• Actually, the Doctor doesn't have a regeneration limit. However, they have had their memories periodically erased for a truly insane span of time because the Time Lords didn't want them to figure this out.

Ruth is the Second Doctor

The 12th Doctor has made it clear, that the Doctor was a young boy at the start, and went to the Academy as a young man, when he met the Master. The interior design of her TARDIS suggests she is from a point in the Doctor’s life close to Hartnell’s incarnation.

• If you imagine that the Doctor regenerated a certain amount of time after escaping from Gallifrey, that would make her the second, Hartnell the third, and so on.
  • Somehow, the Doctor did not have a regeneration limit before Trenzalore. Presumably, the regeneration energy that the Time Lords give him, was only to trigger a regeneration that was already going to happen. This was likely done so that the Doctor wouldn’t become suspicious, as to whatever circumstances explain this.
• You'd need a reason why the TARDIS is shaped like a police box, since they expressed surprise in "An Unearthly Child" that the exterior hadn't changed.
  • That's simple; The TARDIS is sentient, and has decided on one of their previous visits to Earth(specifically London) that she likes the police box look. Additionally, the TARDIS might have changed from its classic cylindrical shape to police box when she recognized a later version of "her thief" standing next to another, and made herself look recognizable, so the Doctor gets the point of Ruth being the Doctor ASAP.
    • Regarding why Ruth doesn't seem surprised when she sees this design, the TARDIS probably made itself a police box in a weird place at least once before (and then went back to working again). Maybe..the chameleon circuit was never broken, it's just been a such a long time since the TARDIS disguised itself properly, no version of the Doctor suspected anything beyond a malfunction. The idea Donna comes up with, in "Journey' End" is really just how to coerce the TARDIS to behave.
• Jossed; she's actually one of the Doctor's many, many pre-Hartnell incarnations who they were given Laser-Guided Amnesia of.

The Meta-Crisis did not count as a regeneration

If this were true, the Ruth incarnation of the Doctor could exist between the 2nd and 3rd or 6th and 7th Doctors without violating the regeneration limit. The Doctor just thought the Meta-Crisis counted because he had forgotten about Ruth.

• It likely does count as a regeneration. It's just that the Doctor, unlike other Time Lords and unbeknownst to them, does not actually have a limit to how many regenerations they have.

Whatever's happening with Ruth is related to the Valeyard

Maybe Ruth is actually the Valeyard, and will become a villain later, explaining her harsh attitude compared to other Doctors. Or, maybe Thirteen is actually the unwitting Valeyard and Ruth is the legitimate Doctor. Yet another possibility is that the Valeyard was actually the Thirteenth Doctor of a previous regeneration cycle, or which Ruth is a part.

• The Valeyard was described as coming "between the Doctor's twelfth and final regenerations." At the time, everyone assumed there was only one time that could refer to, because no one got more than thirteen lives. Now, it's basically just any time between the second Tennant incarnation and whatever ends up being the last incarnation the Doctor has, whenever that ends up being.
  • Except if the Doctor had a past regeneration cycle, then maybe "the twelfth incarnation" was part of that cycle.
• Jossed.

The Lone Cyberman's plan is to go back to the dawn of humanity and convert the first humans

The Lone Cyberman was apparently traveling back in time to restore the Cybermen, and this would be an excellent way to conquer all of humanity.

• Or go to the dawn of the Mondasians and convert the first Mondasian.
• As of "The Timeless Children", Jossed. The Lone Cyberman's plan is to retrieve the Cyberium sent into Earth's past, then use it to wipe out the last traces of humanity.

Based on above speculation that Ruth!Doctor is a canon Two-And-A-Halfth Doctor

The reason the Doctor does not remember her is because she discovers something the CIA and Gallifrey absolutely do not want her to know, and so force a regeneration and wipe all evidence of that incarnation from the Doctor's mind, adding another regeneration to their cycle so they won't notice they've used yet another up - so they won't end up looking for the same answers (this could possibly coincide with the decision to wipe the Doctor's ability to fly the TARDIS and exile them to Earth with the Third Doctor). This is likely to do with the Timeless Child.

• From "The Timeless Children", Jossed and also partially confirmed: it doesn't seem likely that Ruth found out something the Time Lords didn't want her to know, but she was erased from the Doctor's memories because of the Timeless Child: the Doctor is the Timeless Child, and as a result is both much older than they know and is able to regenerate an infinite number of times. The Time Lords regularly erased their memory to keep them from finding this out.

Ruth is from the Doctor's previous regeneration cycle, which includes the past incarnations from "The Brain of Morbius"

The battle with Morbius suggested that the Doctor had (at least) eight incarnations before the First Doctor. Perhaps Ruth is from earlier in the Doctor's previous regeneration cycle, which was reset by the Time Lords when they erased the Doctor's memories and turned him into the First Doctor.

• The long-standing opposing idea is that the other faces seen in that episode were previous faces of Morbius, not the Doctor.
• Per "The Timeless Children", Confirmed: The Doctor is not and never has been subject to a regeneration limit. Over the eons, the Time Lords periodically wiped their memories of their past lives to keep them under their control and believing they were an ordinary Time Lord. Ruth and the "Morbius" faces are all past lives that the Doctor was made to forget this way.

The High Council lied about regeneration limitations.

The only way to excise the issue of Ruth being a past Doctor in this timeline is that there was never a regeneration limit to begin with. We know that the Doc started as a young boy, and One is an old man, but for Ruth to not be remembered but One is, means that at some point, the Doctor regenerated into Ruth, then forgot her. The only issue is that there are already 12 Doctors in the first regen set: 11 numbered and the War Doctor, and Eleven says the Metacrisis was a regeneration. For Ruth to have existed in the past, the Metacrisis doesn't count as a regeneration.

The question now becomes, where does she fit in the timeline? And what caused her to hide with a Chameleon Arc in the first place?

• I find this fake limit a bit pushing it. Wouldn't the Master have found out? How could you keep that under wraps?
  • As another theory further up the page suggests, perhaps only the Doctor specifically doesn't have a regeneration limit, for some as-yet-unknown reason, and the High Council is trying to prevent them from realizing this. Other Time Lords, such as the Master, do have such a limit.
  • A limit clearly exists. The Decayed Master (played by Pratt and Beevers) was the result of the Master trying to extend his life past the natural end of the last incarnation in his original cycle, and Azmael, the Doctor's mentor, died after inducing a regeneration whilst in his thirteenth incarnation in The Twin Dilemma. The only reason these examples occurred is because of the presence of a limit.
• The limit might be artificial rather than fake. This would fit with Rassilon having "the secret of perpetual regeneration" in "The Five Doctors", not to mention the Minyans being able to regenerate an unlimited number of times in "Underworld". Though given that the Time Lords are able to hand out extra sets of regenerations willy-nilly (both "The Five Doctors" and "The Day of the Doctor"), it seems more like thirteenth regenerations require medical assistance rather than being impossible — so renegades like the Doctor, the Master, and the Rani had to be careful, while Time Lords in good standing like Borusa could regenerate pretty casually until Gallifrey's destruction.
• Per "The Timeless Children", Partially confirmed: the regeneration limit is real. The Doctor, however, is not and has never been bound to it.

Ruth is from a pre-Hartnell regeneration cycle that the Time Lords erased from the Doctor's memory

The Doctors we know from canon are all part of a second regeneration cycle, we know the High Council can grant this as they offered one to The Master in The Five Doctors. Ruth is a Doctor from a preceding full or partial cycle. During this cycle The Doctor worked as an agent of the CIA, perhaps initially willingly but as events in the episode showed they eventually became disillusioned and fled, using the Chameleon Arch to hide out as Ruth Clayton on 21st century Earth. The High Council weren't prepared to accept this and set about having her tracked down leading to the events in the episode and while she escaped at the end of the episode Ruth or a later incarnation was eventually forced to return to Gallifrey and surrender to the Council. As part of a cover up of their black ops scheme the CIA erased all knowledge of "Ruth's" existence from the records and even from her own memory before giving her a second regeneration cycle which is the one we are familiar with. After centuries of living the life of a normal Time Lord and having a family the suppressed memories of their old adventuring days and disgust at the manipulations of the Time Lord rulership built up to the point where the "First" Doctor rebelled and escaped Gallifrey subconsciously going back to a world they'd already spent so much time on, Earth.

Points against this idea are the fact that Ruth's TARDIS is police box-shaped and no mention of Susan (yet?).

• As of "The Timeless Children", this appears quite likely, although it is not explicitly confirmed..

Ruth is a splinter regeneration, created by the Timeless Child myth.

The Doctor is still the Thirteenth Doctor. Ruth is just another version of the same Time Lord. Ok, let me back up.

All the previous regenerations of the Doctors are canon; nothing about the timeline has changed. So then what is Ruth? Simple; another Doctor. This connects to the Timeless Child myth because the knowledge of the Child keeps the existence of the fact that other versions of a Time Lord have splintered all around space and time. So, in keeping with this theory, there are always going to be several Time Lord doppelgangers or clone like entities around space and time; the Gallifreyan Founding Fathers just used the Timeless Child to keep the many other versions of the same Time Lord secret from their people.

• We've already seen something like this with Tom Baker's appearance as The Curator in the Fiftieth Anniversary. Plus, the Master brought up the events of "Logopolis" in "Spyfall"; maybe Ruth is a splinter regeneration of Four.
• Jossed.

Ruth is a future Doctor with missing memories.

The future Doctor had something happen to her that caused her to forget earlier parts of her life, like the destruction of Gallifrey, the way Eight forgot it in the EDA.

• Given that there's some kind of secret tied to the Timeless Child that drove the Master (more) insane, Thirteen may have voluntarily removed part of her own memory in order to forget.
• As of "The Timeless Children", it's implied she's a past Doctor, but it is not explicitly stated to be so.

The history is being rewritten

Something changed in the far past of Gallifrey, or possibly the entire universe. The change is slowly propagating along the Doctor's timeline. Ruth is the first or second incarnation of the Doctor in this new timeline, and the changes will keep propagating until Thirteen is replaced by another version of herself.

• The Master will be the one doing the changes.
• Jossed.

History was already rewritten.

Ruth is actually a version of the Doctor from a prior timeline, who was ret-gonned by the Time Lords. This was due to her discovering the Dark Secret of the Timeless Child, so they changed history so her predecessor/s regenerated into a different, less nosy Doctor instead. This might not be the only time an incarnation has been erased and replaced by another. Remember Scream of the Shalka? Maybe the Shalka incarnation of the Doctor was what the 8th Doctor was supposed to regenerate into, but the Last Great Time War changed history so he instead got involved in the war and became the War Doctor played by John Hurt. As the Ruth Doctor lacks a sonic screwdriver, but does have the recognizable TARDIS shape, she may be the original 2nd Doctor. That Doctor got caught by the Time Lords earlier than "The War Games". Somehow she made a way to Cross Through to the current timeline.

• Jossed that she's from a different timeline by Chris Chibnall.

All of the time traveling is causing splinter universes

Perhaps something with all the time traveling really does screw things up. The Time Lords had a no interference policy. Mind you, it corrupted into them keeping their power and letting the rest of the universe rot. However, there could have been very good reason for that. You have the Doctor and the Master merrily ricocheting through time and space, flipping the proverbial bird to what could have been a policy set in place for very good reason. "Orphan 55" had Thirteen all but stating alternate time lines were a possibility. Then you have cases like Clara twisting time and space into knots and unaccounted for weirdness like Morbius and the Valeyard. It's not really a "splinter" universe if none of them are "prime" to begin with.

• Jossed, as Chris Chibnall has stated she's not from an alternate universe.

Ruth is a regeneration of Jenny

Ruth and Thirteen don't recognize one another, because Jenny never met another Doctor after Ten, and Thirteen doesn't believe Jenny survived the Hath War. So if Jenny ended up on Gallifrey, had a run in with someone and fled with a TARDIS,and used a Chameleon Arch to disguise herself, it fits. She and the Doctor share the same exact genetic signature because Jenny was a clone of the Doctor. It also stands to reason that she modeled herself after the Doctor, TARDIS shell and all.

• Jossed.

Missy wasn't lying about the Doctor being a little girl once.

This doesn't necessarily mean that the Doctor was female before leaving Gallifrey. While it's rare, we know that Time Lords can regenerate into different ages, and there's implications that River regenerated into a toddler in America before ending up as a child growing up with her parents across the pond. Perhaps the Doctor regenerated into a little girl, and the Master had at least one encounter with her in that regeneration, a little girl who grew (back) up into the Ruth incarnation.

• As of "The Timeless Children", partially confirmed: as it turns out, the Doctor started as a little girl a very long time ago, but there's no indication that Missy was aware of this at the time.

Ruth is a result of the Metacrisis.

More specifically, Ruth is the Doctor that Tennant would have regenerated into, if he hadn't shunted the regeneration energy elsewhere.Still trying to guess at how she wound up here and now, without appearing before this. any ideas?

• Jossed.

The Doctor was given extra regenerations in "The War Games".

We don't see him regenerate in full, so there could be incarnations between 2 and 3 (or if you want to stretch, 6 and 7). While the Doctor did use up his regenerations by "The Time of the Doctor", who's to say that he only remembers 13 regenerations? The Ruth Doctor is a secret Doctor that the Time Lords never wanted anyone, much less the Doctor himself, to know. Probably because she was the one to discover the Dark Secret of the Timeless Child. To Un-person this (and maybe more in-between) Doctor, once they're done with the Doctor they add at least one regeneration so no-one's the wiser. That way if the Doctor only regenerates 12 or less times before running out of lives, he and other Time Lords never get suspicious.

• This is already covered above, mostly in the sixth WMG down.
• Per "The Timeless Children", Jossed the Doctor has never actually been given extra regenerations because they are not actually bound by the twelve-regeneration limit, and never have been.

Ruth comes between the War Doctor and Eccleston's Ninth Doctor.

I don't rate this one likely, for many reasons already elucidated above, but it seems to be the only potential gap not yet stated. We do see the War Doctor start to regenerate on-screen, but since they couldn't get Eccleston to participate, they don't actually show who the War Doctor turns into. We cut away before the transformation is complete. So, it's theoretically possible that he instead turned into Ruth's Doctor. We did see the War Doctor with his own sonic screwdriver, but he clearly didn't use it for nearly as many Swiss Army purposes and was scornful of how his successors waved theirs about.

• At the very least, it would explain Ruth's more apparently ruthless behavior as a remnant of the War Doctor's characterization.
• Jossed.

Ruth is the real Thirteenth Doctor and Whittaker's Doctor is the Fourteenth Doctor.

• Technically speaking, that would make Ruth the "real" fourteenth Doctor.
• Jossed.

Ruth is a creation of the Trickster.

This may be a bit of a stretch, as it’s unlikely that we’ll ever see the Trickster again, but since this would be amazing if it were true then I’ll present my evidence.

Firstly, Jack and Ruth appearing in the same episode in two separate subplots implies that there is some sort of connection (albeit this one is clutching at straws a bit). Could it be that what the Lone Cyberman wants is an audience with the Trickster, and that Ruth is somehow involved with that? It could be that the Lone Cyberman asks for the Trickster to make the Doctor on the run from the Time Lords or be involved in events other than the Cybermen, leading to a different set of regenerations and the Cybermen empire triumphing in this scenario. We know that the Trickster is capable of this as he wipes Sarah Jane from existence in his home series, though only when he comes to people who are absolutely desperate (and the Lone Cyberman, by its muddy appearance in the trailers and the state that Jack says the Cyberman empire is). And besides, Chibnall himself has said that Ruth IS the Doctor and not from a parallel universe and why would he make the potentially very controversial move of inserting another new incarnation between Doctors (even the War Doctor was fairly polarising)? The only other explanation would be someone editing the Doctor’s home timeline, and the Trickster has the power to do that.

As for how this ties in with the Timeless Child, it’s either the Trickster himself (as the final episode is called the Timeless Children, which may refer to the entire Pantheon of Discord if this is the case, plus the Trickster may exist outside of normal time due to his power to edit it) or a dirty job the Time Lords had him do plus the Cyberman Empire he creates (fits in with the Timeless Children thing again as the Children could be all the new, different lives and Cybermen this act creates, as they wouldn’t exist in the unedited timeline). Further evidence for the Trickster being the Timeless Child is that K9 describes the location him, the Doctor, Luke, Rani and Clyde are sent to in "The Wedding of Sarah Jane Smith" as “nowhere, NOWHEN”, implying that it is a timeless location!

Though it’s unlikely that the Trickster will return, we have seen characters from the spinoffs return in a significant way before, such as Luke, Gwen and Ianto in "The Stolen Earth", Luke in "The End of Time" and the Star Whales in "The Beast Below", so there is the slightest chance that this could happen (though it’s still unlikely).

• And now we have further evidence courtesy of "The Haunting of Villa Diodati". The Doctor notes that none of the stuff is going on should be happening and that SOMEONE sent back the Cyberium to mess with the past. The dilemma between giving the Lone Cyberman what it wants and letting Percy back is also a particularly tricky one to solve, and the Trickster could have made this scenario deliberately to make it difficult for the Doctor to get away without changing history. Sadly, this josses the Trickster being who the Lone Cyberman wants, but the Cyberium could have records of a way to contact him.
• Jossed.

The Lone Cyberman will have a completely innocent sounding desire, making it that much harder to refuse giving it what it wants

The Doctor will go against her companions and acquiesce to the Cyberman’d demands, leading into the finale and driving a rift between her and the Fam that will lead to their eventual exit.

• As of "Ascension of the Cybermen", Jossed: The Cyberman is after a powerful AI that contains the entire history of the Cybermen, and the Doctor is forced to give it up after a Sadistic Choice involving the death of an important historical figure and the potential destruction of the Earth.

Ruth's Doctor won't remember her encounter with the Thirteenth Doctor

If Ruth is indeed a past incarnation, she'll forget about the Thirteenth Doctor as soon as her TARDIS dematerializes. It's been established in previous episodes that when multiple incarnations of the same Time Lord meet, only the one that comes last chronologically will retain memories of the encounter. This is apparently due to the time lines being "out of sync" during these encounters. Thus, Ruth won't remember the Thirteenth Doctor saying that Gallifrey was destroyed and since Gat was killed, that knowledge will die with her. Incidentally, the fact that the Thirteenth Doctor does remember meeting Ruth is a strong indication that Ruth is in her past.

Ruth's TARDIS and its police box exterior

On the face of it, Ruth's TARDIS looking like a police box makes no sense given that she's pre-Hartnell. But "The Doctor's Wife" provides a possible explanation. In that episode, the TARDIS was given the ability to speak and we learn that she perceives time differently. She tells the Doctor that she knows what future console rooms look like even though they don't exist yet. Assuming Ruth's TARDIS is the same one, maybe she chose the police box form because she knows the Doctor will like it in the future.

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