UNIT troops engage the Autons while the Doctor and the Brigadier pursue the Master into the facility's control room.

UNIT troops are lured into the caves and commence a battle with the Silurians while the younger Silurian takes the Doctor to the reactor control room along with Liz and the Brigadier.

UNIT troops proceed to Think Tank's atomic shelter, but are held off by its automated defences.

With K1 apparently disabled, the Doctor and the UNIT troops make their way into the bunker.

It places Sarah on a rooftop as a pitched battle takes place between K1 and the UNIT troops while the Doctor races back with the virus.

Meanwhile, UNIT troops are staging an evacuation.

The Doctor and Frost entered Evening's empire with UNIT troops and managed to destroy the illusion, sending Evening into an irrecoverable coma.

The next morning, the Brigadier has the UNIT troops lay explosives and detonate the whole mine pithead, to the Doctor's fury.

The menace defeated, UNIT troops and environmentalists gather at the Nuthutch for a celebration made all the more special when Jo and Jones announce they are getting married.

The UNIT troops sweep through the nearby forest, and fire on the Zygon.

They become trapped between the two Cybermen and the insane one, until the latter, being irrational, attacks the other Cybermen: fresh UNIT troops wipe out the surviving Cybermen with hand grenades.

Meanwhile, Brigadier Lethbridge-Stewart and the troops of UNIT are handling the security arrangements for the first World Peace Conference.

UNIT troops take control of the prison, killing Mailer and the other leading rioters.

They move towards London, but are confronted by UNIT troops, led by Lieutenant Colonel Speedwell.

The device is confiscated by UNIT, which imprisons Sato until she is pardoned and recruited into Torchwood by Jack Harkness.

Auton was also the first BBV production to have no Doctor Who guest stars at all, after Nicholas Courtney ( who would have reprised his Doctor Who role as UNIT commander Brigadier Lethbridge-Stewart ) was forced by ill health to withdraw from the project.

With Courtney out, the focus of the series was the original character of Lockwood, an enigmatic UNIT agent played by Michael Wade.

This is the second serial to feature the journalist Sarah Jane Smith as the Doctor's travelling companion, and the penultimate appearance by UNIT regular Capt Mike Yates.

The Doctor and Sarah Jane Smith arrive in a deserted London plagued by looters and lawlessness, where UNIT is assisting in maintaining martial law.

The Doctor and Sarah are arrested on suspicion of looting, but are rescued by Brigadier Lethbridge-Stewart who is heading the UNIT operation, and the Doctor begins to combat the monsters, which have necessitated the evacuation.

He is being aided by Captain Mike Yates from UNIT, who is recovering from a nervous breakdown caused by events depicted in The Green Death.

During a meeting of the Extinction Team, the Phoenix Five reveal to Magneto, Storm, Psylocke and Danger ( who is still controlled by UNIT ) that Mister Sinister is the one who told Hope about the Phoenix Force, and ponder on the danger that his goals may represent to the world.

The comic story " Skywatch-7 ", written by Alan McKenzie ( under the pseudonym " Maxwell Stockbridge ") and illustrated by Mick Austin, features a UNIT team encountering a single Zygon at a remote base.

Eventually, they sought to invade the Earth ( in Spearhead from Space ), using more human-looking Autons to replace key government figures, although these plans were thwarted by UNIT with the help of the Doctor, who also destroyed their invasion form, a multi-tentacled cephalopod.

In the first film, a Nestene energy unit and several Autons captured by UNIT in Spearhead from Space are accidentally reactivated.

Though BBV was licensed to use the Nestenes, Autons and UNIT by the writers who created them, as with all spin-off productions the canonicity of these films is unclear.

After a failed attempt at escaping from the hospital ( which results in him nearly being shot dead by an overzealous UNIT trooper ), the Doctor discovers that his TARDIS has been disabled by the Time Lords and he is trapped on Earth.

Baker, still convinced that the answer lies in the caves, overpowers the UNIT man guarding the sickbay and enters them by himself.

One BBC Books novel, The Face of the Enemy by David A. McIntee ( 1998 ), picks up the story of Ian and Barbara, now married to each other, in the early 1970s, the two of them collaborating with the Doctor's colleagues at UNIT and his enemy the Master when Ian is hired as the Third Doctor's temporary replacement while the Doctor is taking a trip away from Earth.

In the Big Finish Productions audio drama UNIT: The Wasting ( 2005 ), Commodore Sullivan ( who is working with NATO ) is called on by the Brigadier for a favour but does not have a speaking part.

*" UNIT Christmas Parties: Ships That Pass " by Karen Dunn ( Short Trips: A Christmas Treasury )

The series ' budget was also increasingly strained by the cost of exotic sets, costumes and props every time the Doctor visited a new setting, and so Bryant and Sherwin ( now effectively acting as co-producer, though the BBC refused to credit him as such ) came up with the idea of reducing the cost of the series by setting all of the adventures on Earth, with the Doctor to act as the Scientific Advisor to an organisation called UNIT, the United Nations Intelligence Taskforce, charged with defending the Earth from alien invasion.

* Valiant ( Doctor Who ), airborne aircraft carrier controlled by UNIT in Doctor Who

* In the Doctor Who spin-off series Torchwood episode " Fragments ", genius Toshiko Sato's backstory reveals that she stole faulty designs from the Ministry of Defence and UNIT, which she used to construct a sonic device, referred to as a " sonic modulator ", to trade to a terrorist organisation in exchange for her mother.

In " The Stolen Earth ", It is revealed that UNIT has been experimenting with Sontaran teleportation technology in what they call Project Indigo.

In a departure from the Doctor's first two incarnations, Pertwee played the character as an active crusader with a penchant for action and fancy clothes, even while the character was exiled on Earth and serving with UNIT.

A UNIT officer states that the Doctor's death must have been too quick to allow for regeneration.

For instance, the BBC television series Doctor Who has spawned two such examples, the fictional military organization UNIT stationed terrestrially to defend modern earth against invasion and a more secretive group Torchwood, who defend the United Kingdom against alien incursions.

UNIT has appeared multiple times in Doctor Who when drastic events are involved, whilst Torchwood is the focus of a successful spin-off series.

BBV's next series was a spin-off from two Doctor Who stories in the 1970s in which the Doctor assisted the United Nations Intelligence Taskforce ( UNIT ) in defeating the Autons, robotic invaders sent to conquer Earth on behalf of the alien Nestenes.

* UNIT 731: Japanese Experimentation Camp ( 1937-1945 )— information site.

* In the Doctor Who episodes " The Sound of Drums ", " Last of the Time Lords ", " The Poison Sky " and " The Stolen Earth ", the UNIT airborne aircraft carrier Valiant bears a close resemblance to Cloudbase.

In UNIT: The Coup ( 2004 ), the Silurians attempt to finally make peace with the humans, though the general public believes it to be a stunt involving men in rubber suits.

In UNIT: The Wasting ( 2005 ), Silurians aid UNIT in finding a cure for a deadly plague.

Finch tries to discredit the Doctor, who will not support the plan ; but the Doctor realises that Yates is the traitor within UNIT.

Sergeant Benton lets the Doctor escape, and when he is recaptured the Brigadier asserts his authority to take the Doctor into UNIT custody rather than the regular Army ’ s.

Back at UNIT HQ, the crisis is over but there are still problems to deal with.

UNIT: The Coup had previously been given away with an issue of Doctor Who Magazine.

To date, this has included several Doctor Who stories, as well as stories from the UNIT and Bernice Summerfield series.