Doctor Who: 10 Theories About What Happens To The Fourteenth Doctor

Alternatively, what if the Fourteenth Doctor does regenerate, but into a whole other Doctor?

As established, the premise of the bi-generation is that the Doctor’s previous incarnations carry on existing, each in their own splinter timeline.

But what if it’s bigger than that? What if the bi-generated Doctors all regenerate into additional incarnations, creating a massive web of Doctor variants?

Perhaps this is how we explain away bonus incarnations, such as the alternate Ninth Doctors seen in The Curse of Fatal Death and Scream of the Shalka. In the prime timeline, Paul McGann regenerates into John Hurt. But perhaps, in an alternate timeline, the bi-generated Eighth Doctor becomes Rowan Atkinson.

And in another timeline, the bi-generated Seventh Doctor becomes an alternate Eighth Doctor… who, in turn, becomes Richard E. Grant.

This would mean that the Fourteenth Doctor could regenerate into literally anyone, not just Ncuti Gatwa, which would also solve the problem of what Fourteen's regeneration looks like. He doesn't have to be pulled through time to the events of The Giggle, he just regenerates normally, wherever he is.