The latest season of Doctor Who revealed that the Master destroyed Gallifrey after learning the truth about the Timeless Child. Though a new theory suggests he might have had help from an unexpected source.
In an overarching narrative spanning five seasons, former EP Steven Moffat brought Gallifrey back after its destruction in the Last Great Time War. But when the Time Lords returned to the real dimension from the pocket universe, they hid away at the end of time, safe from all the advanced civilizations who’d pose a threat to their society. That all changed when Rassilon, one of the planet’s supposed founders, became obsessed with the prophecy of the Hybrid, though, a creature destined to destroy Gallifrey and “break billions of hearts to heal its own.”
To know the identity of the Hybrid, the Time Lords trapped the 12th Doctor inside his confession dial, where he spent the next 4.5 billion years punching his way out to Gallifrey, going “the long way round.” Now, according to a theory by the folks at ScreenRant, what Peter Capaldi’s incarnation did next may have indirectly assisted the Master in the homeworld’s destruction.
Current Doctor Who showrunner Chris Chibnall hasn’t yet specified how the Master brought the Time Lords to their knees, but as we saw in the series finale, Gallifrey was all but in ruins. Moreover, “The Timeless Children” doesn’t explain when this genocide took place, which makes it difficult to determine how Sacha Dwahan’s sinister villain managed the terrible feat. But the 12th’s actions in the season 9 finale, “Hell Bent,” put the planet in a vulnerable situation.
For one thing, he got rid of Rassilon, who was quite possibly the only person capable of keeping the Master’s madness at bay. And for another, he dismissed the High Council, Gallifrey’s elite who made all the important decisions regarding the future of the race.
What incriminates the 12th in this scenario is that he wasn’t even interested in governing Gallifrey. In fact, after snatching Clara from the Extraction Chamber, the Doctor once again escaped inside a TARDIS, leaving the General and the rest of the Time Lords to fend for themselves. So, whether he meant it or not, Capaldi’s actions left Gallifrey defenceless, ultimately making it easier for the Master to sweep in and destroy them.