The Zygon Invasion (TV story)

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

It served as a sequel to events set up in the 50th Anniversary Special The Day of the Doctor, having a beginning sequence dedicated to the relative plot point of this story.

The episode saw the return of Osgood, curiously after her death in the Series 8 finale Death in Heaven, with this episode revealing that before Missy's Cyberman invasion, Osgood and her Zygon duplicate had gotten so identical to each other that they refused to say which was the Zygon and which was the human, making it unknown which Osgood was actually killed by Missy.

It is effectively the second "companion-lite" story in a row as Clara is revealed to have been kidnapped and replaced with a Zygon duplicate called Bonnie.

It also continued the thematic concept of the Doctor apparently facing death, with the end of the episode setting up yet another opportunity for the Doctor to reflect on his mortality.

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
On 23rd November 2013, three of the Doctor's incarnations -the War, Tenth and Eleventh Doctors formed a peaceful negotiation between UNIT and the survivors of the Zygons. This allowed a treaty for asylum to be granted to the Zygons, allowing them to peacefully coexist on Earth with humans, so long as they took human form. On video, the two Osgoods explain the situation about the peace treaty.

Two years later, in Mexico, UNIT scientist and avid fan of the Doctor, Osgood is seen fleeing from an attack in the town Truth or Consequences, despite being previously murdered by Missy. Osgood hides under a desk inside a police department; she readies to call the Doctor, but decides to text once she hears footsteps. The moment Osgood sends the text, a Zygon grabs her.

Inside the TARDIS, the Doctor is rocking out Amazing Grace on his electric guitar. Hearing the console beeping, he stops playing and rushes over to the monitor to see an incoming message from Osgood: "Nightmare Scenario." The Doctor looks on grimly, realizing that a break in the ceasefire has finally come.

The Doctor is next seen sitting on a swing in a park, trying to call Clara; not wanting to draw attention, he code names himself "Doctor Disco" in his messages. Noticing two identical little girls, the Doctor attempts talking to them; it's revealed that they're the Zygon high command. However, at that moment, the Doctor receives a call from Kate Stewart; he attempts to make her see that it's only a splinter group of Zygons wanting war, not the entirety of the race. Unfortunately, at that moment, the leaders run off and are captured by the splinter group. Left with nothing to do, the Doctor decides to go in to UNIT for more resources.

Meanwhile, Clara is leaving for work and checks her phone, to discover that the Doctor has left over 174 messages on her phone. She starts to listen to her voicemail, but finds a child crying on the stairs of her apartment complex. Learning that he cannot find his parents, Clara follows the child back to his apartment, finding it empty; however, the moment she turns around, the child's parents appear, saying nothing is wrong despite the boy's screams. Clara is concerned by this, but is next seen leaving without much of a care; she calls the Doctor, asking if he seriously called himself "Doctor Disco?"

In the meantime, the Doctor learns about the current situation: the splinter group is holding Osgood hostage in order to get information on the "Osgood Box". Deciding to use his status as President of Earth, the Doctor takes his plane to Mexico, hoping to find Osgood and prevent all-out war. Arriving in Truth or Consequences, the Doctor informs his UNIT troops to avoid killing as much as possible as they are going to need someone to negotiate with. Unfortunately, the troops are tricked by the Zygons, who take the form of their loved ones, and vaporized. Given only ten minutes before UNIT begins bombing the terrorist aliens, the Doctor searches the now empty Zygon base, finding Osgood tied up in the cellar; they barely manage to escape as the bombing begins early. A Zygon returns to kill them and gets knocked out by the debris, allowing easy capture.

Elsewhere, Clara assists the London UNIT branch; they discover the lift in her flat has been secretly modified by Zygons to lead to their underground nest. Unfortunately, its revealed Clara is a Zygon; when she visited the flat early, she was captured and impersonated by a Zygon named Bonnie. Bonnie orders the murder of all the UNIT troops present.

At the same time, Kate is investigating what cased the Zygons to attack. Finding an officer from Truth or Consequences, Kate learns a Zygon had trouble keeping its form, leading to panic. However, Kate then discovers that she's talking to a Zygon, who reverts to its true shape to kill her. Moments, later "Kate" confirms UNIT in North America has been neutralized to Bonnie.

Meanwhile, the Doctor and Osgood chat on the plane, which is heading back to the UK. The Doctor believes that Missy killed the Zygon version of Osgood because the Zygons need the original person they're copying alive to maintain their disguise. However, Osgood reveals that she can be either one (but won't tell which she is), since Zygons only use that method for spying on enemies; if they don't need to copy personalities, Zygons can keep someone's form without them original being alive.

The Doctor interrogates the Zygon, learning that an all-out war is the only thing the splinter group wants; they have infiltrated numerous countries now. At that time, Bonnie is watching the plane fly by; she puts together a rocket launcher, and takes aim. The Doctor calls Clara, only to get Bonnie, learning that he's talking to the leader of the splinter group. However, the Doctor immediately realizes the danger, warning Osgood. Bonnie launches the rocket, saying good-bye to the Doctor.

Cast

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

Uncredited cast

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

The Doctor

 * A portrait of the First Doctor hangs in the Unit Safe House in South London.
 * The Doctor starts calls himself both "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," as happened regularly to UK Prime Minister Harriet Jones.

Clara

 * Clara's voicemail greeting says she's either on the tube or in outer space.
 * The Zygon duplicate of 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.
 * 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".
 * The "Clara" in most of this episode is a Zygon duplicate, making this the second consecutive episode in which Clara has a brief appearance.
 * Peter Capaldi and Rebecca Front previously worked together on .
 * The strong subtext in the story concerning contemporary immigration and terrorism has been noted by many commentators and reviewers, and has been widely discussed on social media.

Ratings

 * BBC One Overnight: 3.87 million
 * BBC America Overnight: to be added
 * Final UK ratings: 5.76 million

Filming location

 * Fuerteventura ("New Mexico" scenes)

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. She almost detonated a nuclear bomb beneath London when she first encountered the Zygons. (TV: The Day of the Doctor)
 * The Doctor plays his electric guitar. (TV: The Magician's Apprentice, Before the Flood, The Woman Who Lived)
 * Osgood continues her tendency to wear clothing suggestive of outfits worn by the Doctor. (TV: The Day of the Doctor (TV story), Death in Heaven) In this case, she wears question marks on her shirt lapels. She also reminds the Doctor that he used to wear question marks on his clothes (TV: The Leisure Hive-Survival)
 * 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 war, 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 stopped travelling with the Fourth Doctor. (TV: Terror of the Zygons) Harry Sullivan was mentioned as having worked at chemical and biological weapons facility Porton Down. (TV: Mawdryn Undead)
 * 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 fifth occasion that a companion or assistant of the Doctor has been copied by a Zygon: Kate Stewart and Osgood were both copied (TV: The Day of the Doctor), as was Harry Sullivan (TV: Terror of the Zygons) and Lucie Miller. (AUDIO: 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, COMIC: The Fractures) She no longer appears to be living in the same building as seen in TV: Last Christmas.
 * Hybrids are mentioned, referring to the Zygon dopplegangers. (TV: The Magician's Apprentice/The Witch's Familiar, The Girl Who Died)
 * Clara has been impersonated by an enemy before. (PROSE: The Crawling Terror)

DVD releases
to be added

Blu-ray releases
to be added