Overview
"The Zygon Inversion" is the eighth episode of the ninth series of the British science fiction television series Doctor Who. It was first broadcast on BBC One on 7 November 2015, and was written by Peter Harness and Steven Moffat and directed by Daniel Nettheim. The episode is the second of a two-parter, the first being "The Zygon Invasion", which aired on 31 October 2015.
Set in present-day London, the episode involves Bonnie, the leader of a splinter group of shapeshifting aliens called Zygons, taking the form of the Doctor's companion Clara Oswald (played by Jenna Coleman). Bonnie intends to use an object called the Osgood Box to unmask 20 million Zygons on Earth, thereby starting a war against humanity.
Plot
In the present, Bonnie, the leader of a splinter group of shapeshifting Zygons, has taken Clara's form, keeping her body in a pod. Clara finds herself in a dream version of her flat, able to control Bonnie's actions to a small degree due to a telepathic connection between them, giving the Twelfth Doctor and UNIT scientist Osgood time to parachute out of their plane before Bonnie shoots it down.
The Doctor and Osgood land on a beach. Controlling Bonnie's hand, Clara sends a message to the Doctor's phone saying "I'm awake." The Doctor video calls Bonnie. From winks Bonnie exhibits, the Doctor recognises that Clara is telling him her pod is in London. In interrogating Clara via their telepathic connection, Bonnie learns the Osgood Box is in the UNIT Black Archive under the Tower of London. Against the wishes of the Zygons who are not aligned with the splinter group, Bonnie intends to start a war against humanity by using the Osgood Box to unmask 20 million Zygons on Earth. UNIT leader Kate Stewart, having survived the encounter with the Zygon in New Mexico, reconvenes with the Doctor and Osgood in London.
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