WARNING: The following article contains major spoilers for the Season 12 premiere of Doctor Who, “Spyfall,” which aired this Wednesday on BBC.

After exactly a year of being away, Jodie Whittaker’s Thirteenth Doctor has returned in the Season 12 premiere of Doctor Who. Companions Graham, Ryan and Yaz are back for all-new adventures, and the quartet hits the ground running in the new season premiere “Spyfall.”

After taking a quick break from their adventures to touch base and recharge, the Doctor and her companions are thrown right into the middle of a spy adventure that takes them from MI-6 headquarters and the deserts of Australia to a lavish dinner party. As it turns out, a race of mysterious alien spies have infiltrated the Earth, and they have dangerous plans. But that’s not the big surprise of this episode -- no, the big shock comes when the villain behind these aliens is truly revealed.

Yes, the Master has returned!

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The Master is the Doctor’s mortal enemy -- his exact opposite. A Time Lord like the Doctor, the Master is every bit as intelligent, but nefariously evil. Over the course of the BBC series’ 57-year history, the two characters have clashed many times before. Just as the Doctor regenerates, so too does the Master. The character has been famously played by actors such as Roger Delgado, Anthony Ainley, John Simm and, most recently, Michelle Gomez. Now, a new actor can be added to the list: Sacha Dhawan.

In “Spyfall,” the Doctor and her companions get brought into MI-6 by the head of the organization. However, after he gets assassinated, she seeks out an old friend and ally who once worked for MI-6, an agent codenamed “O.” O, played by Dhawan, explains that he once assisted the Doctor in one of the Time Lord’s earlier regenerations. Now, he is the one she drafts in her latest adventure, to uncover an alien plot to secretly infiltrate the Earth.

Doctor Who Season 12 The Master

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However, just before the episode reaches its cliffhanger ending, O reveals himself as the Master, and the one behind the case the Doctor has been investigating. For the time being, it’s unclear if Dhawan’s Master is the latest version of the villain, or an earlier one. After all, Time Lords are time-travelers, and their paths don’t always cross in a linear manner.

Dhawan’s take on the villainous Time Lord recalls John Simm’s cackling Master: he’s mad, he’s dangerous, and he is on the verge of victory. Gone is the frenemy the Doctor had found in Missy. This time, the Master is back to his original roots -- and he is bringing death and chaos with him.

Doctor Who stars Jodie Whittaker as the 13th iteration of the titular Time Lord. Whittaker is joined by co-stars Bradley Walsh, Tosin Cole, Mandip Gill in a series spearheaded by new showrunner Chris Chibnall. Season 12 premieres on Jan. 1, 2020 at 8 p.m. on BBC with a two-part holiday special. The new season and all previous 11 seasons will stream on HBO Max in early 2020.

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