The Zygon Invasion (TV story)

 was the seventh episode of the ninth series of Doctor Who produced by BBC Wales.

This is the first television story to be a sequel to a previous story, in this case the 50th Anniversary Special The Day of the Doctor, having a sequence dedicated to show the beginning of the plot point of this story.

Synopsis
A long time ago, the Doctor made a deal in the Tower of London. 20 million Zygons walk among us, in human form, living undetected in peace and harmony. But cracks are showing in this delicate peace. Humans and Zygons are disappearing. In city apartment blocks, lifts are going missing, and far below the streets of Britain, alien pods are growing in secret caverns. To top it all off, UNIT's scientific advisor, Osgood, sends a desperate message to the Doctor - but since Osgood is long dead, how is that even possible?

The Doctor, Clara and UNIT must scatter across the world in a desperate bid to set her free. But in a world of shape-shifting aliens, who can you trust? And can the world be saved before it's too late?

Plot
to be added

Cast

 * The Doctor - Peter Capaldi
 * Clara - Jenna Coleman
 * Osgood - Ingrid Oliver
 * Kate Stewart - Jemma Redgrave
 * Jac - Jaye Griffiths
 * Claudette - Cleopatra Dickens
 * Jemina - Sasha Dickens
 * Colonel Walsh - Rebecca Front
 * Little boy - Abhishek Singh
 * Little boy's mum - Samila Kularatne
 * Hitchley - Todd Kramer
 * Lisa - Jill Winternitz
 * Norlander - Gretchen Egolf
 * Hitchley's mum - Karen Mann
 * Walsh's son - James Bailey
 * Zygons - Aidan Cook, Tom Wilton, Jack Parker

Uncredited cast

 * Bonnie - Jenna Coleman
 * Voice of the Zygons - Nicholas Briggs

Crew
to be added

The Doctor

 * A portrait of the First Doctor hangs in the Unit Safe House in South London.
 * The Doctor starts calling himself "Doctor Disco" and "Doctor Funkenstein."
 * The Doctor plays Amazing Grace on his guitar.
 * The Doctor refers to Jemima and Claudette as "Monster High" and "Cinderella."
 * When the Doctor introduces himself as "The President of Earth," a UNIT official answers with "Yes, we know who you are," a reference to Harriet Jones.

Clara

 * Clara's voicemail greeting says she's either on the tube or in outer space.
 * Clara says she heard about the TV series Truth or Consequences on the game Trivial Pursuit.

Osgood

 * A poster in Osgood's office says that the White House has appointed an alien ambassador.
 * The Doctor gave the Osgoods an Osgood Box that was only to be used in the Nightmare Scenario and if Operation Double was broken.
 * Osgood has the TARDIS's phone number. She uses a question mark as its contact photo.

Zygons

 * After the Human-Zygon peace treaty, seen in TV: The Day of the Doctor, 20 million Zygons were relocated around the United Kingdom. It quickly became clear that these Zygons had seized control of the UK and had slowly spread across the entire globe.
 * The Zygons have training camps.
 * The Zygons use pods to contain humans.
 * Bonnie uses an A.A.P.L.S. B-Type Transponder weapon to fire at Boat One.
 * Places the Zygons have invaded include the Mexico border, North Asia, West Africa and Australia.

Story notes

 * The Radio Times programme listing was accompanied by a small colour shot of Osgood and the Doctor, with the accompanying caption "Doctor Who / 8.15 p.m. Osgood is snatched by aliens, prompting a round-the-world rescue mission".
 * Given that the "Clara" in most of this episode is a Zygon duplicate, this is the second consecutive episode in which the real Clara is only onscreen for a brief moment.

Ratings

 * BBC One: 3.87m

Filming location

 * Italy ("New Mexico" scenes)

Production errors
to be added

Continuity

 * The human/Zygon treaty is referenced (TV: The Day of the Doctor) Since then, a version of Osgood has died. (TV: Death in Heaven)
 * Kate mentions a previous attempt at invasion by the Zygons which occurred in the 1970s or 1980s. (TV: Terror of the Zygons)
 * Kate still confuses the UNIT timelines. (TV: The Day of the Doctor)
 * The Doctor mentioned that he snogged a Zygon once (as the Tenth Doctor). (TV: The Day of the Doctor)
 * The Doctor and Kate talk about there always having been two Osgoods ever since the ceasefire. (TV: The Day of the Doctor)
 * Kate wants to bomb areas of the Earth, and the Doctor asks if that's always the solution, referring to her last solution to bomb the UK. (TV: The Day of the Doctor)
 * The Doctor plays his electric guitar. (TV: The Magician's Apprentice, Before the Flood, The Woman Who Lived)
 * The Doctor once again mention how the humans are the bad guys.
 * Osgood reminds the Doctor that he used to wear a lot of question marks on his clothes (TV: The Leisure Hive-Survival)
 * One of the Osgoods wears a question mark jumper, an allusion to the Doctor's seventh incarnation. (TV: Time and the Rani)
 * The Doctor says he never stopped wearing question marks as he wears question mark underpants. His eighth incarnation wore question mark boxer shorts, thus suggesting his ninth, tenth, and eleventh incarnations also did. (PROSE: Seeing I, COMIC: The Glorious Dead)
 * A weapon called the Z-67, confiscated by the Doctor, was invented by Harry Sullivan shortly after he left the Fourth Doctor. (TV: Terror of the Zygons)
 * Clara is once again shown has having authority with UNIT up to and including being able to command UNIT soldiers to use deadly force. (TV: The Magician's Apprentice)
 * Clara is kidnapped by the Zygons and replaced with a Zygon duplicate called Bonnie. This is the fourth occasion that a companion or assistant of the Doctor has been copied by a Zygon (Kate Stewart and Osgood were both copied in The Day of the Doctor, whilst Harry Sullivan was copied in Terror of the Zygons and Lucie Miller in The Zygon Who Fell to Earth).
 * The Doctor wears his sonic sunglasses. (TV: The Magician's Apprentice/The Witch's Familiar, Under the Lake/Before the Flood, The Girl Who Died, The Woman Who Lived)
 * The Doctor resumes his title of President of Earth, and requests use of his presidential plane just so he can "ponce around". (TV: Death in Heaven, COMIC: The Hyperion Empire)
 * Clara's flat (or, at least, the building) is seen. (TV: The Time of the Doctor, Listen, Dark Water)
 * Harry Sullivan is mentioned as having worked at Porton Down. (TV: Mawdryn Undead)

DVD releases
to be added

Blu-ray releases
to be added