Why did Ncuti Gatwa leave Doctor Who, and is Billie Piper the new Doctor?

After just two seasons as the iconic Time Lord, Ncuti Gatwa is leaving Doctor Who.

To the shock of fans around the world, Gatwa regenerated in the series finale over the weekend, wrapping up his tenure as the 15th Doctor and opening the door for a new actor to take his place in the TARDIS.

And in an even bigger surprise, it was the face of Billie Piper — best known for playing beloved companion Rose Tyler in the 2005 and 2006 seasons — who lit up the screen.

While the how and why of this new Who are yet to be revealed, hints have been dropped, and fan reactions have been everything from "heartbroken" to ecstatic.

Ncuti Gatwa became beloved by the world as Eric Effiong in Netflix coming-of-age drama Sex Education.

The Rwandan-Scottish actor first appeared in Doctor Who's 60th anniversary special, alongside fan favourite David Tennant. He officially took the helm in earnest in the 2023 Christmas special, and the eight-episode series that followed.

Featuring drag-queen villains and a Regency-era gay love story, the series was fun, imaginative and unafraid to confront the first black Doctor's race head-on.

It was also the series' first collaboration with Disney, who acquired the global streaming rights in 2022.

The reaction to the show becoming "woke" was swift, and Gatwa has received racist and homophobic backlash since the day he was announced in the role of The Doctor.

But diehard fans were quick to point out that the series had always been progressive, and had amassed a legion of queer fans.

From flirty queer icon Captain Jack Harkness in the 00s seasons to the changing role of female companions throughout the 60s and 70s, Doctor Who has consistently reflected the Zeitgeist.

"I think that diversity has always been a part of Doctor Who," Gatwa told ABC Entertainment in April. "I think he's always explored social issues, and has travelled everywhere.

"It's a universe where there's like, green lizard people walking around, so it's definitely part of Doctor Who to have everyone on screen."

Rumours of the 31-year-old being "axed" for being the "wokest ever" Doctor ran rampant even before his second season aired. 

"I don't really know what the headlines are doing," he said at the season's launch.

"I try to stay committed to the task at hand and just do my job. At the end of the day, it's all I can do."

Meanwhile, the BBC fervently denied the claims: "Whilst we never comment on the future of the Doctor, any suggestion that Ncuti Gatwa has been 'axed' is pure fiction."

Gatwa has since revealed it was always his plan to leave the role after just 18 months, alluding to the intense scrutiny as well as a desire to work on other projects.

"It's a role that demands a lot of you, physically and emotionally and mentally. The actors playing The Doctor are only actors playing The Doctor; unfortunately, we are mere mortals.

"I would love to have the energy and the youth to be able to do this full time for the rest of my life, but my knees are telling me it's time," he joked.

Among fan communities, Gatwa was an overwhelmingly popular fixture, with "devastated" viewers expressing anger at his treatment and portrayal, directed at longtime showrunner Russell T Davies (RTD).

Davies was behind the show's modern revamp from 2005 to 2010, taking a 13-year hiatus before returning for Gatwa's era in 2023.

"Overshadowed and underused at every turn by RTD, given no chance to prove himself as The Doctor, and now he's leaving after only [19] stories," one fan wrote.

"His introduction was about David Tennant and now his exit is about Billie Piper."

Others called his quick tenure "disrespectful", and lamented him being the only Doctor not to face the show's iconic Cybermen or Daleks.

"Ncuti Gatwa's brilliance as an actor was the saving grace of a lot of disjointed storytelling … I was beyond captivated by him and it meant the world to me for him to be The Doctor and so unapologetically himself. I'll miss him," one fan wrote.

Viewers were also left disgruntled by the season's new companion Belinda Chandra (Varada Sethu), who was seen as a strong but under-utilised addition.

"Belinda Chandra. A character with so much potential — compassionate, uncertain, a little bit spiky, competent in a new and interesting way, compellingly distrustful of the Doctor," fan magazine Den of Geek said.

"Potential that has, at this point, been mostly wasted."

Chandra's role was overshadowed by returning predecessor Ruby Sunday (Millie Gibson) in the finale, and with Billie Piper set to return, her place moving forward seems uncertain.

Billie Piper was integral to the relaunch of Doctor Who in 2005, starring alongside Christopher Eccleston and then David Tennant as 19-year-old Rose Tyler, a shop assistant living in a council flat with her mum.

After two seasons of adventures with the Time Lord, Rose became trapped in a parallel universe, indefinitely separated from The Doctor.

But, of course, Piper has made numerous guest appearances since then, last appearing in the 2013 50th anniversary special.

While The Doctor usually regenerates into another version of himself, it seems that something timey-wimey occurred in the 2025 finale, and that Piper is more likely to return to her role of Rose.

In an episode that also saw Jodie Whittaker reprise her role as the Time Lord, the credits stipulate: "Ncuti Gatwa as the Doctor. Jodie Whittaker as the Doctor. And introducing Billie Piper."

Piper also took to Instagram to express her excitement about returning to the TARDIS, posing with a white rose and the caption: "A rose is a rose is a rose."

The news has received mixed reactions from fans. While some are calling it "nostalgia bait" solely "to boost ratings", others are "here for" the return of their "favourite companion".

Amid rumours of the show's cancellation, it’s unclear how long fans will have to wait for a new episode, but the BBC appear to have confirmed its longevity, releasing a media statement quoting Russell T Davies: "After 62 years, the Doctor's adventures are only just beginning."