Doctor Who Series 12 spoilers: Which major character returned in Spyfall: Part One?

The new series of Doctor Who opened with a blockbuster story in Spyfall: Part One. But more than that – it also featured the surprise return of a major character…

Wow. That’s all I can say on that major surprise that everyone on Doctor Who kept quiet about. Chris Chibnall had promised that Series 12’s opening story would be big. But we didn’t know how big.

The biggest reveal of the episode centers around O. Played by Sacha Dhawan, O was someone who once worked for MI6 and was a bit of a conspiracy theorist. However, as the only one at MI6 who believed in aliens, he was eventually fired from the organization.

The Doctor and O had briefly met before, at some point during one of the Doctor’s earlier incarnations. So when an alien force was targeting spies all around the world, the Doctor decided to ask for O’s help directly.

O was pretty much as you’d expect. Intelligent but quiet and awkward, O was someone who was clearly amazed by the Doctor and her lifestyle. There was certainly nothing to suggest that he was hiding something. Not until he lied about being a bad sprinter, something the Doctor immediately noticed due to having read his file, which suggested the opposite. And that’s when we found out who O really was…

Sacha Dhawan’s new character turned out to be much, much bigger than we realized..

(Photo by Jeff Spicer/Getty Images)

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The reveal

After being caught out, O’s manner changed. He went from his quiet, awkward self to someone more energetic, manic, even insane. He had clearly enjoyed fooling the Doctor, and it’s not hard to see why. Not only was he the “spy master” behind this huge threat that they were facing. He was also the Master.

This was definitely unexpected. There hadn’t been a single hint that O was in fact such a huge character, or even that the Master was involved in this story. It’s quite a major surprise that Chris Chibnall has pulled off, but it’s a reveal that’s worked brilliantly. Everyone had kept quiet about it, and the BBC hadn’t even hinted that the villain would return in their marketing campaign – a huge refreshing change after how they had completely spoiled Series 10’s biggest surprise by revealing John Simm in the trailer.

But where does Dhawan’s Master come from? Missy had seemingly died by her own hand, or at least, at the hands of her previous incarnation in The Doctor Falls. Did she survive after all and regenerate into Dhawan? Or could he even be an incarnation from before Gomez? We saw Simm’s Master dying, but we didn’t see who he regenerated into. Could the Master be meeting the Doctor out of order?

We can’t wait to find out in Spyfall: Part Two on Sunday!

What did you think of the major reveal? Were you surprised by the Master’s return? Where do you think Sacha Dhawan’s incarnation fits in the Master’s chronology? Let us know in the comments below.