October 2022 saw Jodie Whittaker's time on Doctor Who come to an end in her final episode as the Time Lord, "The Power of the Doctor." While Ncuti Gatwa had been announced to the world as her replacement in the role, the episode ended on a shocking twist when Whittaker's 13th Doctor regenerated into a new incarnation played by David Tennant, who previously portrayed the 10th Doctor. While it had previously been revealed Tennant would be returning to the series for its 60th anniversary in November, it hadn't been revealed that he would be portraying a new incarnation of the Doctor. This marks the first time in the series' history that the Doctor has been seen going through a regeneration only to emerge as a previous iteration of themselves.

Tennant's unprecedented return as the lead of Doctor Who raises a lot of questions. First and foremost, of course, is what this means for Ncuti Gatwa's version of the character, now revealed to be the 15th Doctor. Trailers have offered a fleeting glimpse of Gatwa's incoming Doctor, suggesting he will be appearing in the 60th anniversary specials before he officially takes over at the end of 2023. Exactly how he will factor into the story, however, is not yet clear. The other major question is why the Doctor has returned to a previous face. Additionally, given that this Doctor has a brand-new outfit and is officially the 14th incarnation, fans may be wondering whether Tennant is about to deliver a different take on the Time Lord.

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Arrival of the 14th Doctor, or Return of the 10th Doctor?

David Tennant as the Fourteenth Doctor looks surprised in Doctor Who

Following a brief sneak peek released after "The Power of the Doctor," the first full-length trailer for the Doctor Who specials arriving later in 2023 was recently unveiled. The trailer shows a little more of Tennant's 14th Doctor in action, as well as offering a look at the return of former companion Donna Noble, played by Catherine Tate. While the trailer gives little away, what is shown is enough to surmise that the 14th Doctor is very much the 10th Doctor reborn. This suggests that, for a Time Lord, a face and a personality come as a package deal.

The trailer for this year's three Doctor Who 60th anniversary specials, which precede a festive special starring Ncuti Gatwa as the new Doctor, concludes with the 14th Doctor exclaiming "Allons-y!" as he jumps into a taxi. This French catchphrase -- meaning "let's go" -- was originally uttered by Tennant during his time as the 10th Doctor. The phrase became synonymous with the 10th Doctor. He was even heard reprising it while saving Gallifrey, when Tennant returned opposite his successor, Matt Smith, in the 50th anniversary special "The Day of the Doctor." The fact the catchphrase -- which was unique to the 10th Doctor -- is making a comeback suggests the 14th Doctor is the same man as the 10th Doctor and not just in terms of his appearance.

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David Tennant in Doctor Who.

Historically, with every regeneration, the Doctor's personality has changed along with their appearance. While the 14th Doctor obviously shares a face with the 10th Doctor, fans had been wondering just how far the similarities would run and whether this new incarnation of the Doctor might only resemble his former self on the outside. Some had even suggested Tennant might forego the English accent he previously adopted in the role in favor of his native Scottish accent. Apparently, even the Doctor himself is uncertain on the implications of his latest regeneration, claiming in the trailer "I don't know who I am anymore." However, it now seems clear that Tennant will be reviving the 10th Doctor's stylings for Doctor Who's 60th anniversary.

Doctor Who's 60th Anniversary specials begin November 2023 on Disney+ and BBC One.