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

However, the Master has placed several of the Doctor's enemies in the TARDIS to make things more difficult for the Graak, such as Daleks, Cybermen, Autons, Ice Warriors, Quarks, Sea Devils, Silurians, Sontarans, Yeti and Zygons.

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 made their first appearance in 1973 in the serial The Time Warrior by Robert Holmes, where a Sontaran named Linx is stranded in the Middle Ages.

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 2011 the Sontarans made their first appearance.

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.

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.

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.

* Shakedown: Return of the Sontarans-Reeltime Pictures ' second production involved the return of popular Doctor Who monsters the Sontarans and the Rutans.

The Sontarans are a fictional extraterrestrial race of humanoids from the British science fiction television series Doctor Who, and also seen in spin-off series The Sarah Jane Adventures.

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 )).

Sontarans reproduce asexually and all the Sontarans depicted in the television series are of one gender ( male ).

In both the classic and new series, Sontarans are depicted using spherical or semi-spherical single-occupant spacecraft known as capsules.

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

The origins of the Sontarans have not been revealed in the television series.

One novel in the series, Shakedown, was in fact a novelisation of an independent video production that had featured the Sontarans.

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.

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 ).

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 Experiment, the Fourth Doctor comments that " Sontarans never do anything without a military reason.

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

The Sarah Jane Adventures story The Last Sontaran showed further technological advancements of the modern Sontarans.

The Sontaran homeworld was destroyed in the future during the events of the Seventh Doctor strip Pureblood ( DWM # 193-196 ) but the Sontaran race pool survived, allowing for further cloning ; the strip introduced the concept of " pureblood " Sontarans not born of cloning.

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.

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 ").

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 Sontarans also appeared in a skit for the BBC children's programme Jim'll Fix It titled " A Fix with Sontarans ", along with Colin Baker as the Sixth Doctor and Janet Fielding as Tegan Jovanka.

In " The Pandorica Opens ", some Silurians appear in 102 AD alongside various alien enemies of the Doctor ( including alien Daleks, Sontarans, Nestenes and other species ) to imprison the Doctor in the mythical " Pandorica " in order, as they see it, to save the universe from him.

The Autons returned in the 2010 episode, " The Pandorica Opens ", allying with the Atraxi, Blowfish, Chelonians, Daleks, Drahvin, Draconians, Sontarans, Cybermen, Haemogoth, Judoon, Slitheen, Silurians, Sycorax, Terileptils, Hoix, Roboforms, Uvodni, Zygons and Weevils to trap the Eleventh Doctor.