The final Doctor Who 2022 Special is nearly upon us, and with it, the next regeneration scene in which the 13th Doctor, portrayed by Jodie Whittaker, should regenerate into the 14th Doctor. The fandom has previously speculated that the current Doctor will regenerate into an older version of herself — the iconic 10th Doctor, portrayed by David Tennant — begging the question of why the Doctor is regenerating into himself. Can he/she even do that? In this article, we’ll dive into the subject of Regeneration once again and discuss whether the Doctor can regenerate into himself.
The short answer to this question is, “yes;” the Doctor can regenerate into himself.” However, the Doctor regenerating into himself was never a matter of possibility but rather of probability. So, even though it’s technically possible, the underlying question is how likely is it for the Doctor to regenerate into himself. And to that, we have to say that the chances of that happening are near improbable.
There are several reasons why it’s nearly impossible for the Doctor to regenerate into his/her current or past incarnation. First and foremost is the show’s productional nature of the Regeneration concept, which was introduced very early in the show. It allowed the production team to change the actor if needed and allow the actors to spend a limited time portraying the role without being typecast — though the latter didn’t work for some, they’ll forever be remembered as the Doctor.
But, as the show progressed and changed, so did the Regeneration rules. What was once a Gallifreyan innate ability to effectively cheat death due to trauma, fatigue, or old age, became an ability gained through genetic engineering exclusive to the hierarchical top of the Gallifreyan society — the Time Lords. In the same manner, the number of regenerations became limited to 12, their outcome became somewhat unpredictable, and some Time Lords have mastered the ability and can trigger it at will.
Some in-universe accounts even state that the Regeneration process can be mastered to an extent to which even the outcome can be controlled — but those aren’t officially recognized as canon. Instead, the general consensus is that both the physical and emotional change in each subsequent Regeneration is a response to the previous incarnation’s emotional trauma. However, there’s one instance in which it didn’t happen that way, and the Doctor technically regenerated into himself.
After being shot by the Dalek at the end of The Stolen Earth episode, David Tennant’s Tenth Doctor begins to regenerate. However, at the start of the next episode, The Journey’s End, he redirects the regeneration energy to his severed hand, which was previously cut off. This healed his injuries but prevented his body from changing. Afterward, Donna touched the infused severed hand and became part Time Lord, referred to as DoctorDonna in the canon, and the hand “grew” a new, human clone of the Tenth Doctor — known as the Meta-Crisis Tenth Doctor.
Still, this counted as a whole regeneration, and David Tennant’s Tenth Doctor regenerated into Matt Smith’s Eleventh Doctor. Having spent one Regeneration to basically heal himself, the Eleventh Doctor now believed that he was at the end of his regeneration cycle — he spent all 12 lives and is now an old man in The Time of the Doctor. Admittedly, the show’s canon at the time still hadn’t introduced the Timeless Child concept to the series, so, as far as the canon goes, he was actually at the end of his life — and his ultimate end added more weight to the entire narrative.
He was eventually saved by other Time Lords who had granted him another whole regeneration cycle before it was established that he’s actually a Timeless Child able to live forever, barring accidents. However, considering that all changes in subsequent regenerations are the answer to the emotional trauma of the preceding one, the question is, what would the Doctor have to gain from regenerating into the same incarnation? What type of personality would the 11th Doctor have if the 10th had completed his Regeneration as intended?
Would we still have Matt Smith’s 11th Doctor threatening fights with the Daleks, or would the renewed 10th be just as ruthless in resolving immediate issues and threats as he and the 9th Doctor have been before? The 11th Doctor, though sillier and younger-looking than the 10th, had more mercy for his adversaries and immediate threats, as evident when the Atraxi tried invading Earth. However, he had his own lessons to learn.
Ultimately, Regenerations aren’t just about healing from near-fatal injuries. They are about change and accepting that change. The 10th Doctor’s real Regeneration came at a point in which he had abandoned his vanity and embraced his selflessness. He accepted the change and emerged as someone better. The 11th Doctor became an old man and actually greeted change as his old body started failing him. The 12th Doctor even implied that he might refuse to regenerate once more and simply die as the Master did in Last of the Time Lords.
He then watched his first incarnation struggle with the idea of Regeneration, which, if he had refused, would prevent him from ever becoming what he now is — the 12th Doctor. So, to summarize, he doesn’t regenerate into himself because that would impede his growth. Before each Regeneration, he accepts his oncoming change, the death of his current personality, because that’s the stage he reached in his life. Just as the TARDIS never took him where he wanted but where he was needed, so the regenerations never made him ginger — they made him into what he needed to be.