More detail is given on the battle which took place before Archie ended up in the crater with the German soldier.

The Twelfth Doctor considered that 'they'd dearly love to get that back, having lost their own copy centuries ago.'

Archie inspects the Doctor's VHS recording of 'the Daleks' master plan'.

The First Doctor's exaggerated behaviour is explained as him deliberately annoying the Twelfth Doctor, as he intially didn't like him.

Nardole's glass avatar mentions that Nardole's death would arrive ultimately at the age of 728 years old.

The Twelfth Doctor recalls meeting all the people whose names he uses as nicknames for his first incarnation.

The Twelfth Doctor's ring is identified as his wedding ring in honour of River Song.

In narration, his first name is revealed even earlier.

The Captain reveals his first name much earlier, as he introduces himself to Bill as Archie.

The First Doctor's final words are slightly changed, and more dialogue is added.

The Testimony mention that they know the Doctor's name.

The First Doctor accepts the Twelfth Doctor as a future incarnation much earlier.

They are also attacked by Dalek mutants before entering the tower, and the First Doctor wards them off with the sonic screwdriver.

The conversation between the two Doctors on Villengard is extended the Twelfth Doctor is able to explain to the First what his reasons are for refusing to regenerate.

The Doctor mentally swears by 'the Rivers of Rassilon'.

Nardole also reveals what happened to him aboard the colony ship after the events of The Doctor Falls.

Heather's fate is elaborated upon, and Bill's inability to remember her is addressed.

The Doctor is reunited with Bill, but is she all she seems? And can he hold out against the coming regeneration? Thrown together at their most vulnerable moments, the two Doctors must discover why the snowflakes are suspended in the sky, why a First World War Captain has been lifted from his time stream moments before his death, and who is the mysterious Glass Woman who knows their true name. But as he fights his way through the snowdrifts, he comes across the familiar shape of a blue police box, and a mysterious figure who introduces himself as the Doctor. Still reeling from his encounter with the Cybermen, the First Doctor stumbles through the bitter Antarctic wind, resisting the approaching regeneration with all his strength.

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