Doctor Who's shock Dot and Bubble ending is Ncuti Gatwa's most stunning moment yet

Dot and Bubble, starring guest actress Callie Cooke as Lindy Pepper-Bean, starts with a clear commentary on our addiction to technology, brought to life with the help of some exaggerated social media influencer personas.

Lindy, a resident of Finetime ("where everything is fine all the time"), happily goes about her day encircled in a bubble that tells her where to walk, what to do, and even when to pee. But, outside of the bubble in the real world, monsters are eating her friends one by one – and the Doctor (Gatwa) and Ruby (Millie Gibson) can't reach her.

Thankfully, the episode sees Lindy step up and follow the Doctor's instructions to save herself. But this is certainly not the story we're used to seeing, of a heroic guest star saving the day. Lindy betrays Ricky September (Tom Rhys Harries), cold-heartedly leaving him behind and then lying about what happened to him before a shock ending to the episode shows the residents of Finetime's true colours in a bleak comment on racism.

As the Doctor offers Lindy a spot on board the TARDIS to escape, Lindy matter-of-factly tells the Doctor she can't travel with him.

"You, sir, are not one of us," she says. "You were kind – although it was your duty to save me, obviously. I mean screen to screen contact is just about acceptable but in person? That's impossible."

Hoochy Pie (Niamh Lynch) goes on to refer to the TARDIS as "voodoo" and claims it's their "god-given duty to maintain the standards of Finetime forever". The Doctor's face falls in disbelief, before looking from person to person as he takes in what's being said. Gatwa gives the slightest nod as the Doctor's perception of the situation has to change entirely.

Assuring Lindy she can say and think anything, he pleads with the residents of Finetime to allow him to save their lives as Murray Gold's emotional score swells. But that offer doesn't even register with Lindy and co, who turn their backs on him.

Gatwa masterfully shows the Doctor experiencing a full emotional spectrum – first, outright desperation, as he screams: "But you will die out there and I can save your lives! Now let me!"

As Lindy walks away, the Doctor tremors, wondering what he can possibly say next, what he can do to change their minds. The answer is nothing. With that realisation, he laughs joylessly, before letting out a guttural scream. Still, he doesn't look away but gazes after the residents of Finetime, perhaps still willing them to change their minds, willing for them to let him save them.

As Lindy looks back at the Doctor, we see him standing tall with tears pouring down his face and a haunted look in his eyes as he resigns himself to the situation. Before opening the TARDIS door, he takes one more look at the residents of Finetime departing on their boat. He pauses for a second, before opening the door and leaving Finetime behind for good.

It's quite the pivot at the end of the episode, but one that allows Gatwa the full freedom to show off his acting chops. Season 14 has been quite light on showing off our new Doctor so far – not least because of Gatwa's commitments to finishing Sex Education season 4 while filming.

Both 73 Yards and Dot and Bubble have seen the Doctor largely take a backseat – but that doesn't mean Gatwa can't steal the show at a moment's notice. It's an electric performance from him and one that could very well go down in the Who history books.

He didn't even need a classic Doctor Who monologue to do it – just a few moments with the camera steadily trained on him to show what he's capable of. While he's undoubtedly been great up until now too, this is the moment that echoes back to what showrunner Russell T Davies has said of his jaw-dropping audition.

Every actor plays the Doctor differently and it's been a pleasure to meet Gatwa's cheeky, sensitive, and enigmatic Time Lord – but no moment has shown him quite like this. The rage, the frustration, the disbelief and the pure powerlessness he elicits at this moment are incredibly potent – and even more so when you consider what Gatwa has previously said about how Doctor Who will address race.

Gatwa is the first permanent Black Doctor in the show's history – following Jo Martin's brief appearance as the Fugitive Doctor during the Chris Chibnall era. Previously opening up about whether the show would address race, he told The Hollywood Reporter: "I think that there will be no way to not, you have to address race."

He added: "I think, like, the Doctor has been... this is the first time the Doctor has been this Black for this long, and he tends to spend most of his time on Earth, it's a favourite of his.

"And so, yeah, it would be essential to explore race within his tenure. It's something that I would want to do and, like, I don't think you can ignore it. You can't ignore my chocolate-ness!"

Of course, there have been references to the Doctor's race already within season 14 – but this is the most prominent time so far this season that the topic of racism has been tackled.

Doctor Who has always been progressive and has never been shy to tackle social issues, but even after 60 years on screen, Gatwa's casting became a topic of conversation. Of course, Gatwa has dealt with it with grace, telling Attitude: “It's not something I'll avidly keep up on. The hate? It is kind of fascinating to me because there's so much energy they're putting into it."

He added: "I think they need to go find a hobby is one thing. But another thing is that we do see a shift happening in casting, in positions of power and in the status quo. I mean, not a fast shift, things could tip over the other way a little bit quicker, but you see people kind of malfunctioning because things are changing."

But, really, the nay-sayers don't have a choice. Doctor Who will always continue to tackle important conversations, as it always has, and with an actor as skilled as Gatwa at the helm of the show, the possibilities are wide open.

Doctor Who continues on Saturday 8th June on BBC iPlayer and BBC One. Previous seasons are available to stream on BBC iPlayer.

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