Doctor Who fans were left shocked after Ncuti Gatwa's Doctor regenerated in a shock twist.

The two-part season finale saw Gatwa's 15th Doctor face fellow Time Lady the Rani in a battle to save the world.

It ended with the Doctor regenerating once again, changing into none other than former companion star Billie Piper.

However, keen-eyed fans have spotted that Piper, known for her role as Rose Tyler, may not be the new Doctor.

Ncuti Gatwa pictured regenerating in his final episode of Doctor Who (Image: BBC Studios/Bad Wolf/James Pardon/PA Wire)

While it is confirmed that Ncuti Gatwa has left Doctor Who and has regenerated into Billie Piper, some are not sure she is the next Doctor.

In the end credits, it........

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