Professional ratings
Review scores
Source	Rating
Rotten Tomatoes (Tomatometer)	83%
Rotten Tomatoes (Average Score)	8.0
The A.V. Club	A-
Paste Magazine	9.0
SFX Magazine
TV Fanatic
IGN	9.3
New York Magazine
Radio Times

"Hell Bent" is the twelfth and final episode of the ninth series of the British science fiction television series Doctor Who. It was first broadcast on BBC One on 5 December 2015.

This episode sees the return of Ohila and the Sisterhood of Karn after previously appearing in the ninth series premiere "The Magician's Apprentice". This episode also sees the return of Gallifrey and the Time Lords, after last appearing in "The Day of the Doctor", while also briefly featuring the Daleks, the Weeping Angels, and the Cybermen. The episode marks the final appearance of Jenna Coleman as Clara Oswald.

In Nevada, the Doctor enters a diner and encounters a waitress physically identical to Clara Oswald. Neither one appears to recognise the other. He begins to tell her a "story" about Clara. As the Doctor narrates, the episode flashes back to Gallifrey, where the Doctor has escaped from his Confession Dial, setting off the Cloister Bells in the city that alert the Time Lord President, the High Council, and the Sisterhood of Karn. They try to summon the Doctor to them, but he refuses their overtures. The President then attempts to have the Doctor executed, but others, including the Gallifreyan military, see him as a war hero. Instead, they help to exile the President, who is revealed to be Rassilon, and the High Council. The Doctor learns that he had been trapped in the Confession Dial for over 4 billion years by Rassilon, to force him to reveal the identity of the Hybrid of Gallifreyan prophecies, destined to conquer Gallifrey and stand in its ruins. The General and Ohila attempt to learn more about the Hybrid from the Doctor, but the Doctor claims he must consult Clara Oswald about it.

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Wikipedia