Under the Lake

"Under the Lake" is the third episode of the ninth series of the British science fiction television series Doctor Who. It was first broadcast on BBC One on 3 October 2015. It is the first part of a two-part story, the second of which is "Before the Flood" on 10 October; both were written by Toby Whithouse and directed by Daniel O'Hara. The episode is set in a Scottish underwater mining facility in 2119, where alien time traveller the Doctor (Peter Capaldi) and his companion Clara Oswald (Jenna Coleman) arrive three days after the crew have unearthed an empty black spaceship. The crew members then start dying, and the survivors find themselves faced with an army of hollow-eyed homicidal ghosts. In the form of Prentis, played by Paul Kaye, this episode sees a return for the Tivolians, a race last seen in the 2011 episode "The God Complex", also written by Toby Whithouse. Plot The crew of an underwater mining facility in Caithness, Scotland in 2119 discover an alien craft in the ruins of a submerged town. They bring it aboard only to find it is missing one of its two power cells, and four glyphs carved into the interior walls. Suddenly the craft's engines ignite, and Commander Moran is killed in the act of pushing another out of the way. Later, the crew finds two ghostly figures, Moran and an unidentified alien, roaming during the night cycle, soundlessly chanting before turning to attack the crew. The crew take shelter in the base's Faraday cage which the ghosts cannot enter.