Fourteenth Doctor

The third of the "skinny man" iterations, the Fourteenth Doctor embraced the second chance he had in regenerating back into the body of his tenth incarnation, as he sought to respond to all the calls of adventure.

A day to come
When encountering the "Vortex Butterfly", the Tenth Doctor was cryptically told that he would not be "limited" to "thirteen lives". (COMIC: )

When the Eleventh Doctor met the Curator in the Under Gallery and quipped how he "never forget[s] a face", the Curator cryptically replied that he "might find [him]self revisiting a few" in the "years to come", though only "old favourites". (TV: )

When Captain Lundvik threatened to shoot him, the Twelfth Doctor speculated that he would "keep on regenerating forever" if he was executed. (TV: ) would later state his own uncertainty to the number of regenerations the Doctor had been granted, (TV: ) with  and  also considering their own uncertainty when debating whether to throw the Twelfth Doctor off a roof, believing they "could [be] up and down the stairs all night." (TV: )

The Twelfth Doctor was forced through seven false regenerations by a "regeneration vampire". With the assistance of the Eleventh Doctor, the regeneration energy he expended was returned to him. (AUDIO: )

While facing being shot by guards of the Good Doctor, the Thirteenth Doctor claimed any attempt on her life would result in "a miracle". (PROSE: ) She later considered regenerating to generate residual artron energy. (PROSE: )

At the conclusion of the Flux Offensive, after the embodiment of Time disintegrated the Ravagers and Azure, the Thirteenth Doctor was warned that her "time [was] heading to its end". (TV: ) The Thirteenth Doctor later wrote a book about all of her lives to aid the her next incarnation if they "[felt] weird" after regeneration. (PROSE: )

The Thirteenth Doctor remarked to Cleo Proctor that she would stand up again if she "clobber[ed]" her, remarking that she would regenerate "possibly several times". (AUDIO: )

Hijacked by the Master
The Thirteenth Doctor was made to undergo a forced regeneration into her fourteenth incarnation in a chamber by the Spy Master, who used the energies of a Qurunx as a power source for a cyber-conversion planet that allowed him to obtain energy to hijack the Doctor's regeneration and insert himself as her fourteenth incarnation. However, due to a fail-safe the Doctor had enacted before her regeneration, the Holo-Doctor was able to work in conjunction with Yaz Khan, Tegan Jovanka and Ace to undue the Master's Dalek Plan, with Inston-Vee Vinder helping Yaz to force the Master back into the chamber so that they could use the CyberMasters' regeneration energy to get the Master to degenerate back into the Thirteenth Doctor, returning him to his original body. (TV: )

Post-regeneration
After the Doctor freed the Qurunx so it could destroy the cyber-conversion planet, the Master spitefully used his Tissue Compression Eliminator to redirect the Qurunx's destructive blast at the Doctor, fatally wounding her. Staving off the regeneration long enough to have a final conversation with Yaz, the Doctor then traveled alone to a cliff overlooking the sea, where she could enjoy the sunrise before she regenerated. Making peace with herself, the Doctor began to regenerate, with her outfit morphing into a completely different set of clothes with her. (TV: ) After the regeneration completed, the Fourteenth Doctor ran his tongue over his teeth (PROSE: ) and found himself taken aback by the fact that he was in a body remarkably identical to his tenth incarnation, (TV: ) thinking how he should be "somebody new" instead of "somebody [he'd] been before", and also thought that his clothes changing too was "weird". (PROSE: )

After returning to the TARDIS, (COMIC: ) the Doctor wrote a letter to the readers of an annual as he continued to question why he had regenerated back into an old body. While he acknowledged that he had new braincells, he wrote that he had regained his old teeth, hands, "fantastic" hair, "slightly quizzical left eyebrow" and "brilliant" grin, concluding that it was nice to have this face back, but that he was still unsure as to why. As he wrote down how his clothes had also changed for the first time since the First Doctor's renewal, he got distracted by something "making a right old racket" on the opposite side of the TARDIS control console. (PROSE: )

The first adventure
Seeing that the noise was a distress signal, the Doctor followed it to what seemed to be Wembley Stadium during the 1966 World Cup Final, where he found what he thought were time tourists watching the historical football tournament, using psychic shields to cover the fact they were a family of purple aliens. However, when a Dalek flying saucer appeared in the sky and started deploying a force of Bronze Daleks to start an invasion, the Doctor focused his efforts on getting the Supreme Dalek's attention so that the Daleks would abandon their attack in an attempt to exterminate him instead. Fleeing back to the TARDIS, the Doctor was handed the World Cup's Jules Rimet Trophy by Georgy Gold, who had mistook him for the police. Not having enough time for explanations, the Doctor bundled Georgy into the safety of the TARDIS, only for a Dalek saucer to seize it before he could follow her in, leaving him surrounded by the Daleks as the Supreme Dalek ordered them to exterminate him.

However, their blasts had no effect, surprising both them and the Doctor. With both wanting answers, the Doctor let himself be taken aboard the Dalek saucer, where he bargained for the invasion to be stopped in return for providing an explanation to the Supreme Dalek after scanning himself with the sonic screwdriver, which the Supreme Dalek agreed to. After scanning the Daleks, the Doctor realised that they were simulacra of real Daleks and and that he was in a simulation, though the Supreme Dalek refused to believe him and destroyed the Earth to prove they were real. However, Claire and Claudine then materialised on the bridge, captured the Doctor and teleported him away, as the Daleks watched in confusion, to the Dalek Dome, where the Doctor met Georgette Gold and learnt he had been in an attraction at a theme park based on Dalek history.

As Georgette showed him the attractions, the Doctor continuously voiced his displeasure at how the "suffering of countless billions" was being made a "fun day out for the family". When Georgette revealed she had lured him in with the distress signal, the Doctor attempted to return to his TARDIS until Georgette told him he couldn't return to the 66-scape until the psychoplasm had been vented, so he followed her to a control room and discovered Kaled mutants sleeping in tanks, with the one designated Specimen Six Sigma waking up, which the Doctor realised was due to his questioning of the Daleks' existence in the 1966 simulation, prompting Georgette to shut it down, depositing the TARDIS in the lobby. The Doctor rushed to the TARDIS, where they discovered Georgy, who was Georgette's simulacra in the 66-space, had been forced to let the Supreme Dalek into the ship in order for it to survive the shutdown and escape into reality.

The Doctor tried to convince the Supreme Dalek the Daleks were still fakes by scanning them with his sonic screwdriver, only for the the Supreme Dalek to have one if its guards destroy it, with the gathering crowd convinced they were watching a live show and asking to be exterminated, ignoring the Doctor's warnings. However, it soon became apparent that the Daleks were becoming anatomically unstable and would soon dissolve once the residue from the artron energy in the TARDIS dissipated, along with Georgy. Unable to stop a tearful Georgy from running off due to needing to focus on the Daleks, the Doctor kept them distracted until they melted away, but was then forced to leave the Dalek Dome by the staff when he continued to advocate its closing.

As he planned to skip ahead in time, the Doctor was drawn into the Dalek Dome's Golden City Zone by Georgy, who had allied herself with the Golden Dalek Emperor in order to find a way for the simulacra to become real, and could only watch as a Dalek interrogator used a hypno-pulse in conjunction with Georgy's connection to her to hypnotise Georgette into transmitting the hypno-pulse into the Dalek Dome and allow the Golden Emperor to gain control as it began constructing a quantum-powered reality gate to enable it's escape from the simulation. However, the Doctor managed to trick the Golden Emperor into revealing its plan of conquest to Georgy, and she severed the hypnotic link to the Dome, though she was swiftly killed. As the Golden Emperor explained it would harvest the psychoplasm of the other Dalek Zones, the Doctor was rescued by Georgette, Claire and Claudine, and they escaped to a zone governed by the Dalek Emperor of the Dalek City, who the Doctor convinced to ally with him and a Dalek Alliance in order to stop the Golden Emperor, though the Alliance's attempt to destroy the Golden Emperor only incited chaos.

Taking control of the situation, the Doctor teleported himself into the Golden Emperor's control centre and arranged the destruction of the quantum-powered reality gate, causing the psychoscape to collapse as he escaped in his TARDIS, which also destroyed the Daleks attacking the Earth. As Georgette lamented the destruction the Daleks had caused while free in reality, the Doctor left it up to her what to do with Dalek Dome as he made his leave. However, he found that the Jules Rimet Trophy that Georgy had left on the TARDIS control console had also melted, and he pondered if the fast return switch had been compromised. (COMIC: )

After the TARDIS crash-landed on Skaro (TV: ) from the compromised fast return switch, (COMIC: ) the Doctor emerged to greet Castavillian and ponder aloud why he had regenerated back into an "old face", only to discover that the TARDIS had collided with a Dalek in a Mark III Travel Machine casing and torn its multi-dextrous claw clean off, as he thought aloud about his fortunate at not being exterminated during the "genesis of the Daleks". Once he realised that Castavillian had been recording down his musings, and that he was creating a bootstrap paradox, the Doctor went to leave, but stopped to replace the multi-dextrous claw with a plunger before he left. (TV: )

Enjoying a second chance
The Doctor landed in a Sycorax spaceship, (COMIC: Into Control) where he saved a Strombok in peril and rescued scared Vega Raptons from a pig he named Alfredo. As he and Alfredo rescued some humans and Sarnsquids, (PROSE: Under Control) the Doctor found himself facing the Queen of the Sycorax, who planned to use blood control and the blood taken from the blade that cut off the Tenth Doctor's hand to force the Doctor to take the place of the Sarnsquids that were moving her ship. However, because he had diffrent blood from his tenth incarnation, the Doctor was able to resist the blood control and duelled the Queen until Alfredo knocked her into the ship's bile pit, with the Sycorax Queen teleporting away to escape the vengeful Sarnsquids. As the Sarnsquids took control of the ship, the Doctor urged all the lifeforms aboard to use it to get home as he left with Alfredo, saying that they should make the most of "second chances". (COMIC: Into Control)

When the Master attempted to force all the incarnations to the Doctor to regenerate at once, the Fourteenth Doctor's head was mixed with his twelfth, fifth, and eighth incarnations' faces, and a human was tasked with identifying each incarnation to repair the timeline. (GAME: )

Renewed adventures with Donna
The Doctor reunited with Donna Noble and her family "a big way" at around the time that Rose Noble discovered a Meep, and Sylvia Noble was "frantic with worry", knowing that Donna could die if she remembered the Doctor. (PROSE: )

Following a rupture in time that resulted in the creation of multiple versions of reality, the Doctor asked a human to examine two pictures of the Toymaker to determine the differences. (GAME: )

Death
The Fourteenth Doctor was eventually succeeded by his fifteenth incarnation. (PROSE: )

Other realities
In the Daft Dimension, the Fourteenth Doctor, referred to as an "old Doctor", was mentioned in announcements about Doctor Who. (COMIC: ) He later met his tenth incarnation at a birthday party. (COMIC: )

Personality
The Fourteenth Doctor opened his arms up to friendships of all sorts, (TV: ) offering a greeting as a show of friendliness, (COMIC: ) as he moved to help all those he found in trouble. (PROSE: )

While he was initially surprised to have the same appearance as the Tenth Doctor, (TV: ) the Fourteenth Doctor quickly adapted to having his old body, immediately looking to "respond to calls" of adventure. When he set himself up with a difficult task, he would look to find ways of making his mission easier on himself, though he was unafraid to do things "the hard way" when dealing with uncooperative people, though he would prefer to "chat" to solve an issue.

He was quick to act when it came to saving people, hastily using himself as bait to draw the Daleks away from the crowd at Wembley Stadium, but could forget vital information when in the heat of the moment. While he would not be intentionally offensive, he was unafraid to use risqué humour. He would also leave people whom were in the midst of a breakdown to focus on dealing with larger and more immediate threats.

He still held some of the vanity of his tenth incarnation, asking for an applause from the audience at the Dalek Dome when they mistook his defeat of the Simulacra Daleks for a rehearsed performance. He also rudely rebuffed the Dalek Dome staff when they refused his instructions to close the show down, and returned smugly when he thought they had called him back.

He had an underlined darkness to him, threatening the Daleks with non-existence when it looked like they had destroyed Earth to prove a point, and smiling as he taunted the Golden Emperor's inability to escape destruction due to the size of his casing preventing him entering the TARDIS. (COMIC: )

He liked caves. (PROSE: )

Continuing the blasé attitude his tenth incarnation showed towards them, the Fourteenth Doctor called the Daleks "nasty children in metal suits", and elevated himself as a "grown-up" in comparison to them. He tried to belittle the Supreme Dalek by calling it "Di Ross", and then took joy in its inability to shoot him. (COMIC: )

Habits and quirks
He often explained his jokes and wordplay, and made a habit of assigning cheeky nicknames to others. (COMIC: )

Skills
The Doctor had the agility to outrun pursing Daleks while simultaneously avoiding their gunstick fire. (COMIC: ) He also possessed the swordsmanship skills needed to fight off the Queen of the Sycorax. (COMIC: )

He could determine the date by smelling the air, (COMIC: ) and focus all his senses to pinpoint the origin of a sound. (PROSE: ) He could also analyse blood by taste. (COMIC: )

Without the aid of the TARDIS's translation circuit, the Doctor could speak German. (COMIC: )

Appearance
The Fourteenth Doctor greatly resembled a slightly older version of his tenth incarnation, sharing his tall, slim frame, finely boned hands and face, and large, dark brown eyes, as well as his thick brown hair with sideburns, though with a slight copper tinge. (TV: ) He instantly recognised the similarity from running his tongue over his teeth (PROSE: ) and by the familiar feeling of his face, which also had a five-o'clock shadow of stubble. (TV: )

His kidneys remained their normal blue colour, (COMIC: ) but he had distinct braincells (PROSE: ) and blood to his other incarnations. (COMIC: )

The Fourteenth Doctor was pleased to have regained the hands he "hadn't realised he had missed", familiar face, "fantastic" hair, "slightly quizzical left eyebrow", and "brilliant grin". (PROSE: )

Main attires
As his clothes manifested with him from his predecessor's regeneration, the Fourteenth Doctor emerged wearing a navy blue trenchcoat over a white button-up shirt, with grey knitted tie, brown and turquoise checkered-tartan trousers and a loose fitting waistcoat with lapels, and grey Converse shoes. (TV: ) He also owned a pair of tortoise shell glasses. (COMIC: )

Casting

 * Having previously portrayed the Tenth Doctor prior to his tenure as the fourteenth incarnation, David Tennant holds the distinction of being the first actor to have portrayed two different numbered incarnations of the Doctor in a mainline story of Doctor Who without needing to fill in for an actor playing the new incarnation, following Sylvester McCoy filling in for the Sixth Doctor during his regeneration scene in Time and the Rani in addition to his main role as the Seventh Doctor, Paul McGann briefly acting as a body double for John Hurt's War Doctor in the closing moments of The Night of the Doctor after the regeneration of his Doctor, Tom Baker and Colin Baker portraying the Curator alongside their original incarnations, and Richard E Grant playing both the Tenth Doctor in The Curse of Fatal Death and the Ninth Doctor in Scream of the Shalka.
 * The idea of the Doctor regenerating into a prior incarnation's likeness was previously proposed by series creator Sydney Newman during a 1986 meeting with BBC One controller Michael Grade, who asked Newman for ways to reformat the program after Colin Baker was dismissed from the role of the Sixth Doctor. According to the 1996 book Doctor Who – The Eighties, Newman specifically envisioned Patrick Troughton, who previously played the Second Doctor, portraying the Seventh Doctor for a single season before regenerating into a female eighth incarnation.

Regeneration

 * The Fourteenth Doctor is the first incarnation since the Second Doctor to emerge from their regeneration with a new outfit. This deviation from the usual norm of the newly-regenerated Doctor still donning the clothes worn by their predecessor led to some confusion among viewers until Russell T Davies clarified that "[he] was very certain that [he] didn't want David [Tennant] to appear in Jodie [Whittaker]'s costume", explaining that his reason for the Doctor's clothes changing during regeneration was to avoid stereotyping "the notion of men dressing in 'women's clothes', [and] the notion of drag", describing it as a "very delicate" matter, expressing that "it has to be done with immense thought and respect", and that the media would make it "look like mockery" of that culture, especially as David Tennant is taller than Jodie Whittaker.
 * The Fourteenth Doctor is the first Doctor to have their immediate post-regeneration story be depicted in a medium other than television, in the form of the Doctor Who Magazine comic story, Liberation of the Daleks.

In popular culture

 * Following the post-regeneration scene in The Power of the Doctor, the Fourteenth Doctor appeared as a character-skin in the free multiplayer battle royale video game Fall Guys, released on 1 November 2022.
 * Tennant portrayed a Doctor in the Fourteenth Doctor's clothing in the Red Nose Day sketch Comic Relief 2023, which saw Lenny Henry suddenly burst into a full on regeneration from stomach pains while preparing to host the Comic Relief live-show, and transform into Tennant, in a partial re-enactment of his scene in The Power of the Doctor, who runs off when he notices he has to host the show. However, Henry being listed as playing the 9.5th Doctor brings ambiguity on whether Tennant was meant to be playing the Fourteenth Doctor or his previous Tenth Doctor character.

Other matters

 * The Fourteenth Doctor's numbered designation was officially confirmed by Russell T Davies in an article posted to the official Doctor Who website following the broadcast of The Power of the Doctor.