"Dark Water" is the eleventh episode of the eighth series of the British science fiction television programme Doctor Who. The episode was written by showrunner and head writer Steven Moffat and is the first of a two-part story; the concluding episode is "Death in Heaven", the finale of the eighth series. It was first broadcast on BBC One on 1 November 2014.

In the episode, Danny Pink (Samuel Anderson) is killed, and finds himself in the Nethersphere. As the Doctor (Peter Capaldi) and his companion Clara Oswald (Jenna Coleman) try to find Danny, they find themselves in a facility that accommodates Cybermen, run by recurring character Missy (Michelle Gomez). In the episode's climax, Missy reveals her true identity as a female incarnation of the Doctor's arch-enemy The Master, last seen in the 2009–10 serial The End of Time.

The episode received widespread critical acclaim, with the performances of Capaldi, Gomez, Coleman and Anderson being praised. Critics praised the horror strand of the episode, and, the maturity level of the episode - and the way the darker, more mature and morbid themes were handled.

Clara is talking on her phone to Danny Pink, ready to admit she has still been travelling with the Doctor and that she sincerely loves Danny, when the line goes silent. A stranger picks up and sadly informs Clara that Danny was hit by a passing car and has died.

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