
In this article we start a new retrospective series leading up to the end of David Tennant's days as the Doctor. To begin, we look back a year to see how show runner Russell T Davies seeded the Tenth Doctor's final stories with signs of his impending regeneration.
Up first is the Doctor Who 2008 Christmas Special, The Next Doctor. By the time this special aired on 25 December, David Tennant had already publicly announced his departure from the role of the Doctor on 29 October, 2008. Footage of the announcement from the 2008 National Television Awards appears below.
With the bittersweet revelation that the four 2009 specials would be the Tenth Doctor's last, the broadcast of the 2008 Christmas special two months later held an extra layer of anticipation for fans, particularly as the title was The Next Doctor. Russell T Davies himself was coy and ambiguous in interviews and press releases on the subject and publicity advertising on the 2008 special, such as the cover for Radio Times featured images of this other Doctor, played by actor David Morrissey, in ways to preserve the mystery of his character. The Doctor Who Magazine cover promoting the episode even gave Morrissey's character the appearance that he may have been the actual Next Doctor.

Meanwhile the online community was ablaze with speculation in the lead-up to the special's broadcast, especially after the pre-tiles sequence for the story appeared during the 2008 Children in Need telethon. The presenter of clip tantalized the audience with the reminder of Tennant's future departure from the series and hinted of the possibility that David Morrissey might be the Eleventh Doctor. The Doctor Who CiN 2008 footage appears below.
Following this episode glimpse and the brief sighting of Morrissey's Doctor, Internet rumors flew about like a Christmas blizzard: Some said the "next" Doctor was indeed the Eleventh Doctor crossing his timeline to meet his earlier self; others speculated the other Doctor was an alien out to steal the Doctor's name and fame; yet more others posited he was another Time Lord, possibly an insane Master, hiding in human form based on story photos of Morrissey and Tennant holding a pocket watch (a similar object had been the receptacle for the Master's consciousness in the 2007 series); while more voiced the opinion that Morrissey was a human con-man pretending to be the Doctor.
On a side note, the theory of a human or alien con-man impersonating the Doctor gained particular traction among fans as an earlier story from the Big Finish audio range had featured such a plot. This story, entitled The One Doctor (an obvious similarity in itself to the 2008 Christmas title), had been released as the series's 2001 Christmas adventure, and pitted Colin Baker's Sixth Doctor and his companion Melanie Bush, played by Bonnie Langford, against another "Doctor" and his "companion" Sally-Anne, played respectively by actor Christopher Biggins and actress Clare Buckfield. As it turned out, the other Doctor, equipped with own Psychic Screwdriver and "Stardis," was in fact an impostor named Banto Zame, whom the real Doctor ultimately defeated. The cover for this adventures appears below.
But in the end, David Morrissey proved not to be the Doctor, but a man from 19th Century London named Jackson Lane who had by chance encountered the Cybermen and accidentally absorbed Dalek info-stamp they had stolen, which contained all their information on the real Doctor. The clip (in two parts) featuring this revelation appears below.
And so David Morrissey's ersatz-Doctor was just a man, his sonic screwdriver was in fact a regular screwdriver, his TARDIS was just a hot-air balloon, the fob watch was simple broken timepiece, and after defeating the Cybermen once more, David Tennant was still the Doctor. Fans wondering if Russell T Davies had once again pulled off an unexpected debut of the Eleventh Doctor instead discovered that all was still the same. And yet with a little bit of sly marketing and storytelling, Davies managed to remind viewers that although Tennant was still the Doctor, a change was certainly coming and perhaps not in the happiest circumstances. Below is video in two parts from the conclusion of The Next Doctor, featuring both "Doctors," with the genuine article musing on why he is now alone, and Jackson Lane offering him a bit of Christmas companionship. For the Tenth Doctor, this may have been his last happy Christmas.
As the titles say, the Doctor returned in Easter 2009's Planet of the Dead, and our next articles will take us there. For more articles on the Doctor's upcoming regeneration, please visit here, here, and here. All photos source: Doctor Who Wiki