"Dot and Bubble" may count as one of the greatest fake-outs in Doctor Who history. Just when you think you know what it's about — a Black Mirror parody in which the rich-kid colonists of planet Finetime are so obsessed with their augmented reality social media spheres that they don't notice they're literally being eaten by giant slugs — "Dot and Bubble" throws a curveball.

Turns out Finetime's all-white inhabitants are so prejudiced toward the Doctor (Ncuti Gatwa), they point-blank refuse his offer of a TARDIS rescue and sail off to their doom.

Many fans expected the show would include a depressingly likely incident of racism toward the first Doctor of color in its storyline — but it seemed more likely to arrive in an episode set in Earth's past, like the Regency-era "Rogue" coming up next week. Injecting racism into a futuristic setting is a stark reminder: Enlightened attitudes are never a given.

Still, this is far from the first time Doctor Who went there where TARDIS travel and racism are concerned. Let's unpack that, along with all the other references and Easter eggs in "Dot and Bubble." Starting with the obvious:

"Dot and Bubble" looks a lot like "Nosedive."

Showrunner and writer Russell T Davies has described "Dot and Bubble" as "probably [Doctor Who's] clearest step into Black Mirrorterritory." And it's clear which Black Mirror episode he's referring to: "Nosedive." The pastel colors of Finetime's inhabitants, created by costume designer Pam Downe, consciously echo the look of the 2016 Season 3 opener.

"Nosedive" follows Lacey (Bryce Dallas Howard) through a future in which everyone rates their interactions with each other on a scale of 1 to 5. Lacey, initially obsessed by her social score and blind to basic humanity, eventually breaks out of her state of simpering fear and learns to be authentic.

That's the arc we're led to expect for Lindy Pepper-Bean (Callie Cooke) in "Dot and Bubble": After all, she literally learns to walk on her own without her intermediated Bubble experience.

However, the all-white cast of extras, plus the fact that Lindy would literally rather call the police than talk to a Black man (the Doctor), should clue us in to a different Black Mirror homage — since the world of "Nosedive" did appear to be racially diverse. The Netflix show has tackled racism in episodes such as "Black Museum" and "Demon 79."

"Doctor Who" has talked about race and time travel before.

Predictably, Gatwa's casting as the Fifteenth Doctor led to a racist backlash online, one that the star batted aside: "I think they need to go find a hobby," he told Graham Norton. The show he's helming has not shied away from the issue, with the problems of racism through history being explored via the Doctor's companions.

The first companion of color, Martha Jones (Freema Agyeman), faced down mildly racist rhetoric from the bard himself in "The Shakespeare Code" (2007), then had to deal with the jokes and attitudes of 1913 Britain in "Human Nature" (2007) while the Doctor (David Tennant) remains hidden inside an oblivious human version of himself.

The Peter Capaldi Doctor was more aware of the problem in "Thin Ice" (2014) when he took Bill Potts (Pearl Mackie) to the Thames Frost Fair of 1814. Bill, who'd just pointed to her "melanin" in the context of a Britain that had not outlawed slavery yet, notes that the inhabitants of Regency London are "a bit more Black than they show in the movies."

"So was Jesus," replies the Doctor. "History's a whitewash."

Later (in the video above), Capaldi encounters a white aristocrat who calls Bill "creature" and "girl" and barks at her to rise "in the presence of your betters" — then lands what has to count as the most satisfying punch in Doctor Whohistory.

But Gatwa's frustration, and his heartbreaking plea to the Finetime inhabitants — call me whatever names you want, just let me save you — surely counts as one of the show's most devastating moments ever.

"Dot and Bubble" makes similar references to "73 Yards."

In the previous episode, "73 Yards," we noted a connection to another Russell T Davies Doctor Who story about a future fascist Britain, "Turn Left." Is it a coincidence, then, that the first movement instruction we see in Lindy Pepper-Bean's Bubble tells her to turn left?

Similarly, the name of one of Lindy's friends, Vivienne Nook, echoes a name used by Davies in "Years and Years": Vivienne Rook (Emma Thompson) was the name of the fascist prime minister. And in "The Sound of Drums," also referenced in "73 Yards," an investigative journalist called Vivien Rook uncovers the evil schemes of Prime Minister Harold Saxon, aka The Master (John Simm).

Coincidence again? Is there such a thing in a show that is clearly building up to something with multiple appearances by Susan Twist, who plays Lindy's mother here? Could Davies be doubling down on references to unstable autocrats for a reason?

That Dot looks familiar to "Red Dwarf" fans.

The device creating that AR bubble of screens around Finetime inhabitants ... well, let's say it looks nothing like the Apple Vision Pro, a headset with its own Black Mirror vibes.

The dot is a tiny antigravity device that appears to hover in thin air until a user commands "dot down, bubble off" — and can also be lethal at high speed (RIP Ricky September).

We haven't seen such a device in Doctor Who before — but we have in the BBC sci-fi comedy series Red Dwarf (1988-2020). It's called a "light bee," and it's used to create a hologram of deceased crewmember Arnold Rimmer (Chris Barrie) — a character almost as annoyingly egotistical as Lindy Pepper-Bean.

The light bee's glitches formed the basis of many Red Dwarfstorylines (as in the above video), though at least it never tried to lead Rimmer into the gaping maw of a giant slug.

How to watch:New episodes of Doctor Whodrop every Friday night at 7 p.m. ET on Disney+, where available, and simultaneously at midnight on BBC iPlayer in the UK. The two-part season finale airs June 22, and will also be screened in UK theaters.