The final two episodes of Doctor Who season 15 brought some major threats and twists. The biggest was the ending to the season, which sees another change of face.
Caution: This post contains SPOILERS from the Doctor Who season 15 finale.
By now, you likely know that Ncuti Gatwa has finished his role as The Doctor. The end of Doctor Who season 15 brought a surprise regeneration, with Billie Piper becoming Sixteen. Of course, there are now questions about when we'll get to see her step in the role as The Doctor after being the first companion of the revival series back in 2005, because Doctor Who season 16 is not yet officially confirmed.
However, it looks like the initial plan was not for Gatwa to regenerate. As IGN shares, Gatwa talked to Graham Norton in 2024 to share that filming for the new season would start in 2025. That was cut from the broadcast, but people in the audience heard him say it loud and clear. With the season not confirmed, it looks like something has happened behind the scenes, and that has led to some reshoots.

Doctor Who season 15 wrapped filming in May 2024
We know that originally, the current season had finished filming in May 2024. In fact, there was a still on the Disney+ platform of Fifteen and Belinda dancing at a party, which never ended up making it to air. On top of that, Archie Lal was cast as Belinda's father and was supposed to appear in the finale. He didn't make it, with Belinda's mom explaining that he was elsewhere.
This coincides with news that there was some filming happening back in February 2025 at the place that would become Belinda's house. It's possible that Gatwa decided that he couldn't wait for Disney and BBC to renew the series, so opted to pursue other projects, leading to a need to find a reason for him to regenerate.
With the final episode feeling rushed toward the end with the half-cocked mission to save Poppy, it does feel like some late writing needed to happen. It's possible that initially, Belinda was going to stick with Fifteen for a while, but as Gatwa potentially made a decision to leave, it meant a whole change for companion as well.
There are a lot of threads from Doctor Who seasons 14 and 15 now left open with this sudden departure and the reshoots. They could be explained a little with Piper's Sixteen, but usually, these types of threads are forgotten about.
Doctor Who is available to stream on Disney+.
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