Season 12 of Doctor Who has been a hell of a ride. The adventures of Jodie Whittaker's Thirteenth Doctor hit the ground running when the Master returned in the two-part season premiere. Since then, it's been one exciting quest after the other. The Doctor and her companions visited Earth years after it became uninhabitable; met Nikola Tesla and Thomas Edison; took on a platoon of Judoon near the Moon; met another, mysterious version of the Doctor; and stopped a dangerous alien virus from wiping out the Earth.And through all of this, the Doctor has been coping with the loss of her planet, Gallifrey, the death of the Time Lords and the mystery of the Timeless Child. There are only four episodes left in the season, and the BBC has released the titles for the two-part finale: "Ascension of the Cybermen" and "The Timeless Children."

So what do these titles tell us about the end of Season 12?

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Let's start with Season 12's penultimate episode, "Ascension of the Cybermen." The foreboding title is more than likely connected to a thread that first came up in "Fugitive of the Judoon." In the fifth episode of Season 12, Captain Jack Harkness made his long-awaited return, leaving a message with Graham, Yaz and Ryan for the Doctor to "beware the lone Cyberman." According to the fan-favorite character, the Doctor mustn't give the Cyberman what it wants.

Later, the episode revealed the alien race of androids were a fallen empire. However, episode 11's title suggests the Cybermen may rise again. What's more, given that this episode will pick up on this thread, it's possible Captain Jack will make his return here, where he will hopefully -- and finally -- meet Jodie Whittaker's Thirteenth Doctor.

Meanwhile, the title of the finale, "The Timeless Children" indicates this episode will deal with the mystery of the Timeless Child. This child was first mentioned in the Season 11 episode, "The Ghost Monument," by sentient rags called the Remnants who peered into the Doctor's past -- and the past of the Time Lords themselves.

The mystery returned front and center in Season 12's "Spyfall, Pt. 2," when the Master revealed that what he learned about the Timeless Child is what prompted him to destroy Gallifrey and kill the Time Lords. We don't yet know who or what this child is, but it seems apparent it is connected to the origins of Gallifrey.

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Doctor Who Spyfall Part 2 The Master

In addition, the title of the finale implies that there may be more than one child who is timeless. Or, perhaps this title confirms the theory that the Time Lords stole their immortality and ability to regenerate from this single child. This would, in effect, make the Time Lords the Timeless Children.

However, that remains a theory for now. Hopefully, the Master will return before all is said and done. For the time being, at least we know these final episodes will deal with Season 12's two main mysteries.

Doctor Who stars Jodie Whittaker as the 13th iteration of the titular Time Lord. Whittaker is joined by co-stars Bradley Walsh, Tosin Cole and Mandip Gill in a series spearheaded by showrunner Chris Chibnall. The next episode is set to air on the BBC on Feb. 9. The new season and all previous 11 seasons will stream on HBO Max later this year.

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