Ruby Sunday talks to the Doctor, who has a whistle around his neck.

The history of Doctor Who was forever changed by the season finale episode « Empire of Death » — but not in the way we were expecting.

Despite inspiring a flurry of fan theories about Ruby Sunday‘s mum (could it be Rose?), showrunner Russell T Davies simply gave us the statistically most likely answer. As foreshadowed in « The Legend of Ruby Sunday, » the mystery mother was … an ordinary young woman. Instead of the appearance of Susan the Doctor’s granddaughter, we learned that her name was sprinkled throughout history by Sutekh the Destroyer, god of death.

But that doesn’t mean Whovian brains aren’t exploding at what Davies just casually revealed along the way, starting with this incredible headline:

Sutekh has been hanging around the TARDIS for the last 49 years of Doctor Who.

Ncuti Gatwa in "Doctor Who."
Credit: Disney+

In « Pyramids of Mars » (1975), the only story prior to this season to contain Sutekh, the Doctor (Tom Baker) and Sarah-Jane Smith (Elisabeth Sladen) thought he had trapped his most powerful enemy in a time corridor, where he aged more than 7,000 years. Then they jumped in the TARDIS and quickly left the scene of the trap — a burning priory in 1911 that would one day become UNIT HQ.

But from that point onwards, we now know, Sutekh was wrapped around the TARDIS, « staring into eternity and slowly evolving into my godhood. »

That’s right — every single Doctor Who story from « Pyramids of Mars » to « The Legend of Ruby Sunday » has been irrevocably changed, because each one now contains secret Sutekh.

The Sutekh-on-the-TARDIS era now starts with « The Android Invasion » (1975) and continues for an astonishing 231 more TV stories, including everything in the last 19 « New Who » years of Christopher Eccleston, David Tennant, Matt Smith, Peter Capaldi, Jodie Whittaker, Tennant again, and now Ncuti Gatwa. There are hundreds of implications. To pick just one: When Captain Jack Harkness (John Barrowman) clung to the outside of the TARDIS in « Utopia » (2007), he was riding with Sutekh to the literal end of the universe.

No wonder Gatwa’s Doctor screamed when he thought of all the worlds he’d accidentally infected with Sutekh’s Susan clones. We should too. In watching him do it, oblivious themselves, the TV audiences of the last 49 years are effectively complicit. Name another show that can give you a twist like this!

The twist does, however, also mess with the stories of Sutekh’s return in Doctor Who comics, novels, and Big Finish audio dramas. But hey, you can always head-canon that problem away by saying Sutekh got splintered in time, or some such typical Who explanation.

The Memory TARDIS is now canon.

That ersatz TARDIS held together with « memories and wishes »? Not only is it a fan’s dream, with more Easter eggs than you can wave psychic paper at — such as the « WHO 1 » license plate from the Doctor’s car Bessie in the Jon Pertwee era, and the classic show’s TARDIS console on the ceiling — it’s also the setting for Tales of the TARDIS, a recent BBC series that repackages classic multi-part stories in omnibus editions — including, most recently, « Pyramids of Mars. »

In bookend scenes, companions and Doctors from the classic era (all played by their original actors at their current creaky ages) reminisce in the so-called Memory TARDIS. None of the characters know how they got there, except to suggest that the TARDIS itself is dreaming. Now we know why — and Davies can pat himself on the back for placing one of the key moments from the finale in a spin-off that started the previous year.

How to watch: Tales of the Tardis is streaming on BBC iPlayer in the UK. No word yet on when or even if Tales of the TARDIS will ever land on Disney+, though the companion bookend scenes have been uploaded by fans to YouTube.

The Doctor likes to watch himself in « Pyramids of Mars. »

Gatwa’s Doctor spends a good chunk of his first scene with Sutekh staring at the classic Tom Baker story in question. Now at first glance, it may seem strange that this supposed memory of the Doctor’s looks very much like a BBC production from 1975, complete with camera angles and cuts.

But there’s precedent for this, most notably in « Trial of a Time Lord » (1986). In this season-long story, the Doctor (Colin Baker) and his prosecutor the Valeyard (Michael Jayston) argue over multiple new-to-us Doctor adventures while they watch them on a giant projector screen in court. The battered cathode ray tube screen Gatwa is toting at least seems much more Doctor-ish.

How to watch: « Pyramids of Mars » is streaming on BBC iPlayer in the UK and Britbox in the U.S.

Mel misses the Sixth Doctor’s unusual outfit.

Ncuti Gatwa and Bonnie Langford in "Empire of Death."
Ncuti Gatwa and Bonnie Langford in « Empire of Death. » Credit: Disney+

Speaking of Colin Baker, his polka-dot bow tie and his eyesore of a multicolored coat is front and center in the Memory TARDIS — which explains why Melanie Bush (Bonnie Langford) has a nostalgic moment when she sees them.

Mel was introduced in « Trial of a Time Lord, » but lost that version of the Doctor in the very next story when he regenerated into the Seventh Doctor, Sylvester McCoy. Was this her way of saying McCoy should have kept the coat?

The Doctor has history with spoons… and whistles.

The spoon that the Doctor procures on a distant planet is far from the first to appear in the show. McCoy’s Doctor, like McCoy himself, liked to play the spoons. Peter Capaldi’s Doctor once dueled Robin Hood in a wonderfully silly spoon-on-sword fight. And Jodie Whittaker’s Doctor melted Sheffield steel spoons to make her sonic screwdriver.

But that’s nothing compared to the Doctor’s love of (literal) dog whistles. He used one many times in the Tom Baker era, sometimes to summon his robot dog K-9 and sometimes to incapacitate or annoy military figures and officials. The fact that it was a dog whistle should have been a clue to the Doctor’s plan to drag Sutekh through the Time Vortex like Mitt Romney with the family dog.

The Beatles teased the ending of « Empire of Death. »

The Beatles in "The Devil's Chord."
The Beatles in « The Devil’s Chord. » Credit: Disney+

« My dog is alive, he’s not dead, » the Beatles sang earlier in the season, in « The Devil’s Chord. » At the time it was seen merely as doggerel (pun very much intended), an indication that the world had lost its musical mojo. But the giant invisible dog-headed deity sitting outside the TARDIS on Abbey Road knew differently. If only the Doctor had listened to the Beatles!

Sutekh is cultural appropriation.

Speaking of the dog-headed alien deity, why did he just happen to look like the Egyptian god named Sutekh? « Cultural appropriation, » says the Doctor — a timely reversal of an outdated Who trope.

In « Pyramids of Mars, » Tom Baker’s Doctor says Sutekh was so evil that cultures across the universe designed their gods to look like him — which is, y’know, a bit dismissive of thousands of years of ancient Egyptian history. So it’s fitting that the first Doctor actor born in Africa (Gatwa is Rwandan-Scottish) gets to stand up for the dignity of the continent’s oldest civilization.

73 yards is the radius of the TARDIS’ perception filter!

Aneurin Barnard as Roger ap Gwilliam in "73 Yards."
Aneurin Barnard as Roger ap Gwilliam in « 73 Yards. » Credit: Disney+

Sutekh created all those Susans at the edge of the TARDIS’ perception filter — which the Doctor reveals to be a distance of 66.7 meters. Ruby remembers that this is 73 yards. Which is of course the name of this season’s episode in which an older version of her follows Ruby at this distance for her entire life until she breaks a time loop, erasing her memory of the entire story.

In « 73 Yards, » UNIT commander Kate Stewart (Jemma Redgrave) postulated that the mystery stalker had something to do with the TARDIS’ perception filter. (Confirmed!) That’s also the distance of the CCTV camera that recorded the events on Ruby Road seen in « The Legend of Ruby Sunday. »

We also see Roger ap Gwilliam (Aneurin Barnard), the future fascist Prime Minister from « 73 Yards, » whose genetic database allowed Ruby to find her mum. But that raises a terrifying prospect: if the time loop is broken, and Ruby’s stalker no longer scares Gwilliam into resigning, and Sutekh restored the lives of everyone in that future Britain, does that mean the nuclear-mad PM gets to launch his missiles after all?

More Doctor Who planets than ever got a shout-out.

Skaro, home of the Daleks. Telos, home of the Cybermen. (Well, one of their homes — long story.) The Ood Sphere, home of the Ood. These are just some of the planet that get a shoutout from the Doctor as Sutekh inadvertently restores life to all of them. (Agua Santina, the planet with the woman with the spoon and the baby, is entirely new.)

The others are pretty deep cuts, to put it mildly. Only two are from the New Who era: Messaline from « The Doctor’s Daughter » and Shan Shen from « Turn Left. » The others are all classic show locations: Vortis from « The Web Planet », Tigella from « Meglos, » Calufrax from « The Pirate Planet, » Spiridon from « Planet of the Daleks. »

You could probably watch all these stories, but you might have to be an ancient god wrapped around a TARDIS to have that kind of time on your hands.

How to watch: All Gatwa’s first season of Doctor Who is on Disney+, where available, and on BBC iPlayer in the UK.