Though the two species are never seen together, several references are made to the Rutan Host, an equally militaristic race with whom the Sontarans have been at war for more than 50, 000 years (" The Poison Sky ").

In 2011 the Sontarans made their first appearance.

The Rutans have made appearances in the Missing Adventure novel Lords of the Storm by David A. McIntee and in Terrance Dicks's New Adventure novel Shakedown ( based on the spin-off video Shakedown: Return of the Sontarans, also written by Dicks ).

The Autons, the Master, Omega, the Sontarans, the Silurians and the Sea Devils all made their debut during this period, and the Daleks returned after a five-year absence about halfway through Pertwee's run.

She made a guest appearance on Jim'll Fix It in a Doctor Who related sketch alongside Colin Baker's Doctor in 1985 ( A Fix with Sontarans ).

Sontarans come from a large, dense planet named Sontar in the " southern spiral arm of the galaxy " which has a very strong gravitational field, which explains their compact stocky form.

The Sontarans have an extremely militaristic culture ; every aspect of their society is geared toward warfare, and every experience is viewed in terms of its martial relevance.

Aside from a ritualistic chant in " The Sontaran Strategem "/" The Poison Sky ", they are never seen to engage in any activity that would be considered recreation, though a few offhand comments by Commander Skorr in " The Poison Sky " suggest they do consider hunting a sport ( according to their creator Robert Holmes, Sontarans do have a highly developed artistic culture, but have put it on hold for the duration of the war, while the opening chapter of the novelisation of The Time Warrior, based on Holmes ' incomplete draft, refers to Linx listening to the Sontaran anthem while his spaceship is in flight ).

The Sontarans depicted in the series have detached, smug personalities, and a highly developed sense of honour ; on multiple occasions, the Doctor has used his knowledge of their pride in their species to manipulate them.

Although physically formidable, the Sontarans ' weak spot is the " probic vent " at the back of their neck, through which they draw nutrition.

Human characters in both The Sontaran Experiment and The Sontaran Stratagem comment on how closely individual Sontarans resemble one another ; however, it should be noted that their height, skin tone, facial features, vocal timbre and accent, hair, spacing of teeth and even number of fingers have varied from story to story, and sometimes within stories.

However, their armour is vulnerable to standard human firearms in " The Poison Sky ", but the Sontarans in that episode used a ' cordolane signal ' which caused the copper-lined bullets to expand, jamming most firearms instantly.

The Sontarans make their return in the revived series in the episodes " The Sontaran Strategem " and " The Poison Sky ", with Christopher Ryan playing the Sontaran leader, General Staal of the Tenth Sontaran Battle Fleet and also being the story arc's primary antagonist.

In the episode, the Sontarans attempt to convert Earth into a breeding world for their clones ; a planet the size of Earth would be able to clone millions at a time.

Big Finish Productions first used the Sontarans for their audio drama Heroes of Sontar-a 2011 Fifth Doctor story.

However, believing themselves to be superior, the Sontarans turned on their creators, conquering the planet Sontar and changing it to suit their biology.

Shakedown marks the only occasion in which the Sontarans and their Rutan foes appear on screen together, and was adapted into a Virgin New Adventures novel.

In The Infinity Doctors, the Doctor negotiated a peace between the Sontarans and the Rutan Host when two of them were left trapped in a TARDIS for several hours and got to talking due to their inability to kill each other.

In the full-length New Series Adventures book The Taking of Chelsea 426, by David Llewellyn, the Rutans again appear alongside their enemies the Sontarans.

The Sontarans then headed back to Sontaran space, unknowing that they were carrying Rutans into their territory.

Most recently, they make a surprise appearance in the Sixth Doctor Lost Story, The First Sontarans, battling against their oldest foes.

Writing about the last role, Ben Rawson-Jones reported that " Blake's 7 fans were ... pleased to see their beloved Cally pop up in the film as a random solicitor .... Chappell's most notable post-Cally role in science fiction was in the direct-to-video Doctor Who spinoff Shakedown: Return of the Sontarans in 1995.

* This serial marks a number of firsts: the first appearance of both Sarah Jane Smith and the Sontarans ; the first mention of the name Gallifrey, in reference to the Doctor's home planet ; and the Rutans who would later appear in Horror of Fang Rock.

The Sontarans reproduce by means of cloning rather than sexual reproduction, and thus for the most part are extremely similar in appearance.

Their appearance lead to the attack of the Sontarans on Chelsea 426.

The serial Horror of Fang Rock, set during the early 20th century, hinted that the Sontarans had gained the upper hand, but this proved merely a temporary setback for the Rutans ; " The Poison Sky ", set during the early 21st century, hinted that the Rutans were winning at that point.

The Rutans only appeared on television in the serial Horror of Fang Rock, in which a single Rutan is encountered, though they are mentioned in some serials featuring Sontarans ( The Time Warrior, The Sontaran Experiment, The Two Doctors, The Poison Sky and The Last Sontaran and Enemy of the Bane episodes of Doctor Who spin off The Sarah Jane Adventures ).

These security barriers were breached on occasion by the Sontarans, by manipulating the more technological Vardans, who suborned the Doctor into sabotaging both of these from within ( The Invasion of Time, 1978 ).

They have been killed by targeting that location with a knife ( The Invasion of Time ), a screwdriver (" Shakedown: Return of the Sontarans "), and an arrow ( The Time Warrior ).

All the Sontarans depicted in the television series have monosyllabic names, many beginning with an initial ' st ' sound ( e. g. Styre ( The Sontaran Experiment ), Stor ( The Invasion of Time ), Stike ( The Two Doctors ), Staal ( The Sontaran Stratagem ), and Strax ( A Good Man Goes To War ); exceptions are Linx ( The Time Warrior ), Varl ( The Two Doctors ) Skorr ( The Sontaran Stratagem ) and Kaagh ( The Sarah Jane Adventures )).

" The Doctor also comments in The Invasion of Time that Sontarans can mass-clone themselves at rates up to a million embryos every four minutes.

* As with A Fix with Sontarans, David A. McIntee's Virgin New Adventures novel First Frontier offers the premise that Dimensions in Time was merely a particularly unpleasant nightmare of the Doctor's.

Gallifrey has now been invaded by the Sontarans, led by Commander Stor, who finds Kelner ever ready to pledge support, even if the other Time Lords remain resistant.

It is revealed that the Varden invasion was simply a means to lower the shield in order for the Sontarans to gain control of the Time Lords ' power.

He theorises that the Sontarans also kidnapped Dastari as he is the only biogeneticist in the galaxy who could isolate the symbiotic nuclei that gives Time Lords the molecular stability to travel through time.

She left the series in an emotional farewell scene in 1964 at the conclusion of The Dalek Invasion of Earth, but briefly returned for the 20th anniversary special The Five Doctors in 1983 and also appeared in the 30th anniversary charity special Dimensions in Time and ( as a different character ) the independent Doctor Who spin-off film Shakedown: Return of the Sontarans.

Together with the Doctor, Sharon faced the Daleks, the Sontarans and Brimo the Time Witch, among others.

The Sontarans invade Gallifrey, home of the Time Lords.

Several races with issues with the Time Lords, e. g. the Sontarans, wished to participate but were forbidden to do so.

Years later, at a diplomatic conference, a representative of the Order is murdered by the Sontarans, and the murder is blamed on the Time Lords.

Ross Jenkins in The Sontaran Stratagem describes a Sontaran as resembling " a talking baked potato " but The Doctor sticks up for the Sontarans by saying that, to them, he looks like a pink weasel.

In The Sontaran Stratagem, the Sontarans are seen to create human clones by growing them in tubs of green fluid.

The Two Doctors introduced a weapon called the Meson Gun ( as named in the Jim'll Fix It Sketch, A Fix with Sontarans ), a large silver rifle with a red fuel tank in the centre which was used by Group Marshal Stike and Varl in the third episode.

The Sontarans will next appear in the seventh series of Doctor Who, in an episode penned by Mark Gatiss.

The Sontarans feature in Destiny of the Doctors, a Doctor Who video game released by BBC Multimedia.

The Sontarans have also appeared as a character in the PC game Destiny of the Doctors released on 5 December 1997, by BBC Multimedia.

A Sixth Doctor Lost Story from the mid-1980s, written by Andrew Smith, it features the Sontarans and the Rutans on ninetieth century Earth, tracking down a scientist named Jacob, who escaped through time and space.

Other appearances by the Sontarans include the spin-off videos Mindgame, Shakedown: Return of the Sontarans and Do You Have A License To Save This Planet?

The Sontarans also briefly appear in The Eight Doctors, sent to the Eye of Orion by an agent of the Celestial Intervention Agency to kill the Fifth and Eighth Doctors.

The Fourth Doctor faced the Sontarans in Dragon's Claw ( DWM # 39 -# 45 ), by Steve Moore and Dave Gibbons, where a crew of Sontarans menaced China in 1522 AD.

In Steven Moffat's short story " What I Did on My Christmas Holidays by Sally Sparrow " ( the basis for the Tenth Doctor episode " Blink "), the Ninth Doctor has a rooftop sword fight with two Sontarans in 21st century Istanbul, defeating them with the help of spy Sally Sparrow, apparently before the events of " Rose " in his personal timeline.

The Sontarans also feature in the Kroton solo strip Unnatural Born Killers ( DWM # 277 ) and the Tenth Doctor's comic strip debut The Betrothal of Sontar ( DWM # 365 -# 368 ), by John Tomlinson and Nick Abadzis, where a Sontaran mining rig on the ice planet Serac comes under attack by a mysterious force.

The Rutans were eventually defeated by the Doctor, but had by that time infected a number of the Sontarans as well.