Doctor Who - Empire of Death ending explained: How was Sutekh defeated?

So, how did our heroes fare after season 1’s penultimate episode left them at the mercy of Sutekh, the almighty titan? Was Susan Triad (Susan Twist) simply another harbinger of Sutekh, or something more?

Who was Mrs Flood? And did Ruby Sunday (Millie Gibson) finally unmask her birth mother?

The answers to all of these questions lie below, so read on if you came away from the episode a little fuzzy – we've done our best to unpack that wild and unpredictable rollercoaster ride...

How did Sutekh survive?

In 1975 serial Pyramids of Mars, the Fourth Doctor (Tom Baker) and Sarah Jane Smith (Elisabeth Sladen) first encountered Sutekh, one of a race of Osirans, beings of God-like power who are worshipped by many cultures across the universe, including on Earth in ancient Egypt.

On the planet Mars, the Eye of Horus – an Osiran device beaming a signal that held Sutekh prisoner inside a pyramid on Earth – was destroyed, unleashing the villain, but in a final showdown, the Doctor was able to extend the terminus of the time tunnel down which Sutekh is travelling into the far future.

Sutekh appeared to age rapidly and eventually perish, as the Fifteenth Doctor recalls in Empire of Death: "I cast you into the time vortex – I sent you forward to your own death."

"Instead I found a home," Sutekh explains. "I clung to your infernal machine and for so many years, I hid – I have travelled with you for all this time, riding the spine of your ship, staring into eternity and evolving into my true Godhood."

It appears that Sutekh has had a grip on the TARDIS ever since the events of Pyramids of Mars, existing as a silent, malevolent companion to the Doctor all this time and accompanying the Time Lord on his travels.

How was Sutekh defeated?

Now unleashed, an evolved Sutekh uses the being that was once Susan Triad to unleash his "dust of death" – a horrific substance that extinguishes all life it comes into contact with, starting with Kate Stewart (Jemma Redgrave) and all UNIT personnel, followed by Ruby's adoptive mother Carla Sunday (Michelle Greenidge), Carla's mother Cherry (Angela Wynter) and the enigmatic Mrs Flood (Anita Dobson).

The dust continues to spread until it has consumed all life on Earth – and eventually, the universe.

Sutekh reigns over his empire of death – but the "god of all gods" has an Achilles' heel... his curiosity.

Like the rest of us, Sutekh is unable to see the face of Ruby Sunday's mother and is determined to learn her identity, even keeping the Doctor and Ruby alive as long as it takes to get answers.

Having used a DNA testing programme established in 2046 by sinister prime minister Roger ap Gwilliam (Aneurin Barnard) to finally establish a familial link, Ruby – transported alongside the Doctor to UNIT HQ – teases Sutekh with the reveal of her mother's name, distracting the Osiran just long enough to gain the advantage...

Ruby lassoes Sutekh with "intelligent rope" – recovered earlier from the time window's remembered TARDIS, a version of the craft "made of memories" and "held together by hopes and wishes and luck" – while the Doctor uses a whistle – also found in the remembered TARDIS – to unleash the heart of the TARDIS, vanquish Sutekh's harbinger (Genesis Lynea) and regain control of the ship.

Taking flight, the TARDIS drags Sutekh into the vortex, where the Doctor unleashes his own inner "monster" and leaves his nemesis to die – trapped, Sutekh burns up in the vortex, apparently gone for good this time.

How did everyone come back to life?

Sutekh was defeated, but what about the horrors he'd unleashed across the universe?

Happily, by dragging Sutekh into the vortex – the pathway to all of time and space – the Doctor is able to "bring death to death" and so "bring life". In effect, Sutekh 'kills' the death he had already wrought and life is restored across the universe, with everyone who'd perished – including Kate Stewart, Carla, Cherry, Mrs Flood, and the likes of Melanie Bush (Bonnie Langford), Morris Gibbons (Lenny Rush) and Rose Noble (Yasmin Finney) – all revived.

Who was Susan Twist's character?

Having invaded the TARDIS, Sutekh was exposed to all of the ship's "secrets" – including memories of Susan (Carole Ann Ford), the Doctor's granddaughter.

Inspired, the Osiran "created an apparition of her, universally" – a woman who resembled Susan was brought into existence anywhere the TARDIS landed, with the combined might of Sutekh's power and the TARDIS's perception filter enabling the woman's various guises to be birthed as real beings who fitted into history.

If the TARDIS landed in the same spot more than once – e.g. Earth in 2024 – then the woman would be reborn each time, getting "stronger and stronger" with each reincarnation – hence why the latest iteration, Susan Triad, was a genius and world-renowned tech entrepreneur.

Post-Sutekh's defeat, Susan Triad continues to exist – her history, life and family intact. As Mel explains, "The god of death created life."

It's possible we haven't seen the last of this Susan either, with Kate noting that her "very good brain" could be put to use as UNIT's latest recruit.

Who was Ruby's mother?

Thanks to Roger Ap Gwilliam's system of compulsory DNA testing, the Doctor and Ruby are able to find a record of Ruby's mother and UNIT is later able to use its advanced tech to confirm the familial link.

Ruby's mother is an ordinary human being, one Louise Miller – played by Faye McKeever – who left the infant Ruby at the church on Ruby Road, where she hoped she would be safe. Louise's step-father was "trouble" and the then-teenage mother didn't feel she'd be able to protect her child.

As to how exactly Louise was able to remain hidden from the time window, from Sutekh, from anyone who attempted to see under her hood, it seems that the intense interest in her from such powerful forces somehow reshaped reality around her.

"She was important because we think she's important," the Doctor explained. "The whole of creation was turning around to her [and] it made her sheer existence more powerful than Time Lords and gods. In the end, the most important person in the universe was the most ordinary – a scared little girl, making her baby safe."

Louise wasn't pointing at the Doctor that night, but at the lamppost behind him – she was pointing at the name of the road, indicating her desire to name her child "Ruby".

It's not clear why Louise wore a hooded robe the night she dropped her baby off (purely for the drama?) or how exactly anyone else knew to call Ruby by that name when no-one was around to see Louise point at the sign, but maybe we can chalk that one up to the same cosmic forces that made an ordinary woman so significant and powerful in the first place.

Who was Mrs Flood?

Mrs Flood (Anita Dobson) appeared to simply be the sweet next-door neighbour of Ruby Sunday and her family, but it soon became apparent that there’s much more to the character than meets the eye.

While her character currently remains an enigma, she's likely to be a villain in years to come. After all, she did proclaim that The Doctor’s story “ends in absolute terror” in Empire of Death.

What's next for The Doctor?

Ncuti Gatwa's second season of Doctor Who has already wrapped filming.

But before then, fans have a holiday special to look forward to, which Davies has called "one of the maddest Christmas specials you'll ever see".

Doctor Who will return to BBC One this Christmas. Previous seasons are available to stream on BBC iPlayer.

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