Professional ratings
Review scores
Source	Rating
Rotten Tomatoes (Tomatometer)	100%
Rotten Tomatoes (Average Score)	9.15
The A.V. Club	A
Entertainment Weekly	A-
SFX Magazine
TV Fanatic
IGN	7.9
New York Magazine
Radio Times
Daily Mirror

"The Doctor Falls" is the twelfth and final episode of the tenth series of the British science fiction television series Doctor Who. It is written by Steven Moffat, directed by Rachel Talalay, and was broadcast on 1 July 2017 on BBC One. It is the second episode of a two-part story, the first part being "World Enough and Time". The episode received overwhelmingly positive reviews from television critics.

As a continuation of the previous episode, "The Doctor Falls" concludes the first televised multi-Master story of the show, as well as the origin of the Mondasian Cybermen. In the episode, the Doctor (Peter Capaldi) must save himself and the remaining human population of a gigantic colony ship from the Cybermen, while also dealing with two different incarnations of the Master (Michelle Gomez and John Simm) at once. The episode features a cameo from the First Doctor, now portrayed by David Bradley. He had previously played William Hartnell, the original First Doctor actor, in the 2013 Doctor Who docudrama An Adventure in Space and Time.

Aboard the colony ship reversing from the event horizon of a black hole, the Doctor finds Bill has been converted into a Cyberman. The Master and Missy capture him, but the Doctor had earlier surreptitiously reprogrammed the Cybernet to target Time Lords as well, forcing them to flee. Nardole arrives in a commandeered shuttlecraft to rescue them. The Doctor is electrocuted by a Cyberman, but is saved by Bill.

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Wikipedia