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24 September 2014

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The Sontaran Experiment

Production Code: 4B

First Transmitted

1 - 22/02/1975 17:30

2 - 01/03/1975 17:30


The Doctor, Sarah and Harry arrive on a desolate and apparently deserted Earth to discover that a group of shipwrecked astronauts from a human colony, GalSec, have been lured there by a fake distress call. One of their number, Roth, tells Sarah of an alien conducting gruesome experiments on him and his crewmates. The alien turns out to be a Sontaran, Field-Major Styre, who is compiling a report on human physical and mental capabilities as a prelude to an invasion of Earth.

The Doctor challenges Styre to unarmed combat. The Sontaran agrees but is quickly weakened in Earth's unfamiliar gravity. Harry meanwhile enters Styre's ship and uses the Doctor's sonic screwdriver to remove the vital terullian diode bypass transformer, so that when the alien returns there to revitalise himself he is drained of all his energy and destroyed.

The Doctor sends a message to the Sontaran fleet, warning them that without Styre's report they cannot invade.

Episode Endings

The alien emerges from its ship and removes its helmet. It is a Sontaran.

The Doctor, Sarah and Harry leave Earth via the transmat with the intention of returning to Nerva.


Robot Monster.

Planet of the Apes.

Dialogue Triumphs

Harry : "Doctor! I thought you were dead."

The Doctor : "Not me" [He holds up a piece of metal.] "Piece of the synestic locking mechanism from Nerva's rocket - popped it in my pocket."

Harry : "'Fortuitous"

The Doctor : "Foresight. You never know when these bits and pieces will come in handy. Never throw anything away, Harry." [He throws it away.] "Now, where's my five hundred year diary. I remember jotting some notes on the Sontarans... It's a mistake to clutter one's pockets, Harry."

Vural : "Clock expert?"

The Doctor : "Horologist, actually, and chronometrist. I just love clocks: atomic clocks, quartz clocks, grandfather clocks... Cuckoo clocks..."

Dialogue Disasters

Harry : "I feel a bit like a Morse message: slightly scrambled."


Sarah initially believes Field Major Styre of the Sontaran G3 Military Assessment Survey to be Linx (The Time Warrior). She says that they are identical, which they aren't (Styre's face is paler, squatter, and lacks bristles, and he has five rather than three digits). [As with the tall Sontarans of The Two Doctors, it seems clear that, although a cloned species, a degree of morphological diversity is present. That there is also mental divergence is obvious or else the military ranking system is meaningless.]

The main Sontaran military leadership group is known as the Grand Strategic Council. Styre uses a 'pistol' rather than the typical Sontaran wand. A terrulian diode bypass transformer is a vital part of the 'recharging' equipment used by Sontarans, allowing them to 'feed on pure energy'. Sabotage of this component proves fatal for Styre. The Sontaran robot is also powered by terrulian.

The Doctor thinks that his 500 Year Diary has notes on the Sontarans in it [made, despite partial memory loss, after the events of The Two Doctors?]. The sonic screwdriver is used to repair the transmat spheres and to disable the robot. Mention is made of the vast animal/botanic section on Nerva.


Earth, possibly 'London', in the same period as The Ark in Space.

Future History

By the time of The Ark in Space, Earth has been without any form of animal life for around 10,000 years. However, Earth has been habitable for several thousand years. [The solar flares are not those mentioned in 'The Trial of a Time Lord'.] Nerva, 'the lost colony', has never been found, and has become a legend [as it's in Earth orbit it presumably has some stealth capability].

Other Earth colonies, such as Galsec, have established large empires (such peoples are perhaps the regressive elements mentioned by Vira in The Ark in Space). With humans in control of around half of the galaxy, many of the empires have no time for 'Mother Earth' philosophies (cf. Planet of Evil). It is commonly believed that Earth is still uninhabitable.


This was the first story to be recorded with no interior scenes.

Kevin Lindsay makes his last Doctor Who appearances, playing Styre and the Sontaran Marshal. He died not long afterwards as a result of a long-standing heart condition.

The GalSec astronaut Krans is played by Glyn Jones, the writer of the season two story The Space Museum.

Tom Baker broke his collar bone during the making of this story, and he is consequently doubled by Terry Walsh in many of the scenes where the Doctor is required to move or engage in physical action.


Styre's terrulian diode bypass transformer.


Obvious use is made of stand-ins during the fight with Styre.

During the fight the Sontaran's head is knocked sideways.

Why only send one Sontaran? (Numbers are surely not at a premium in a cloned race?)

And why is Styre experimenting on humans prior to an invasion of Earth when the planet is depopulated anyway?

Fashion Victim

Sarah in her yellow mac and woolly hat? At least it's practical (cf. Jo Grant).

Cast & Crew


The Doctor - Tom Baker

Harry Sullivan - Ian Marter

Sarah Jane Smith - Elisabeth Sladen

Erak - Peter Walshe

Krans - Glyn Jones

Prisoner - Brian Ellis

Roth - Peter Rutherford

Styre / The Marshal - Kevin Lindsay

Vural - Donald Douglas

Zake - Terry Walsh


Director - Rodney Bennett

Assistant Floor Manager - Russ Karel

Costumes - Barbara Kidd

Designer - Roger Murray-Leach

Fight Arranger - Terry Walsh

Incidental Music - Dudley Simpson

Make-Up - Sylvia James

OB Cameraman - unknown

Producer - Philip Hinchcliffe

Production Assistant - Marion McDougall

Production Unit Manager - George Gallacio

Script Editor - Robert Holmes

Special Sounds - Dick Mills

Title Music - Ron Grainer and the BBC Radiophonic Workshop, arranged by Delia Derbyshire

Visual Effects - John Friedlander

Visual Effects - Tony Oxley

Writer - Bob Baker

Writer - Dave Martin

Bottom Line - from The Discontinuity Guide

'It's absolutely typical of Harry. How anyone in his right mind can fall down a whacking great subsidence like that...' The Sontaran Experiment succeeds despite its obvious limitations.

It has a virtual film look, although neither the robot nor the deflection of the Marshal's invasion plans are wholly convincing. The Sontaran Experiment exposes the padding in many Doctor Who stories by completing its narrative with great economy (cf The Awakening).

Analysis - from Doctor Who, the Television Companion

'The Sontaran Experiment is an experiment for the show as well as for Field-Major Styre,' reckoned Nick Pegg in DWB No. 93, dated September 1991. 'The first two-parter for over ten years and the first story shot entirely on OB videotape, it comes across in dramatic terms as a series of heavily stylised statements about where the show is headed under the new line-up. Conventions and expectations which had formed the bedrock of the Pertwee years are yanked from beneath the viewer's feet; the emphasis on such standard lines as "characterisation" and "morality" gives way to what looks like an experiment in pure atmosphere. Untrammelled by the need for complex exposition (because the actual plot is so delightfully nonexistent and silly), the story concentrates on generating a series of effects.'

The idea that a Sontaran battle fleet would hold back from invading a totally uninhabited Earth while a lone Field-Major conducts a lengthy assessment of the ability of humans to withstand an attack is indeed a rather silly one. The revelation that groups of human colonists have 'built an empire' since leaving their planet of origin also sits rather uneasily with the scenario presented in The Ark in Space, in which it was suggested that the sleepers aboard Nerva were the only ones to have survived the solar flares that had supposedly devastated the Earth. These awkwardnesses are neatly glossed over, however, and writers Bob Baker and Dave Martin present a highly entertaining story with just the right amount of plot to fill its unusual two episode length.

It is in terms of atmosphere and imagery that The Sontaran Experiment really triumphs. The tension builds nicely during the first episode with the GalSec crew's hints of an alien menace lurking in the rocks and the ominous sound and eventually sight of an imposing robot patrolling the area, all leading up to the cliffhanger introduction of Styre - initially mistaken by Sarah for The Time Warrior's Linx (although the Sontaran actually looks slightly different on this occasion, with a redesigned mask and five fingers instead of only three). Then in the second episode the story takes on a really horrific quality as the sadistic nature of Styre's tests on his human victims becomes fully apparent. The scene in which Harry finds one of the astronauts left chained up to die of thirst is truly shocking, and the subjection of Sarah to a series of terrifying hallucinations is also, as Pegg put it, 'genuinely sinister' - although perhaps the most gruesome test of all, involving an assessement of human resistance to 'immersion in fluid', is thankfully only heard about rather than seen. The climactic fight scene between the Doctor and Styre is also well done, and the simple but quite effective shot of the Sontaran 'deflating' as the energy drains out of him is another enduring image.

Rodney Bennett makes an excellent debut as a Doctor Who director (The Ark in Space, although the first of his stories to be screened, was actually the second to be made) and the astutely chosen and well used Dartmoor location adds much to the story's atmosphere and effectiveness. It is indeed refreshing to have, for once, a story recorded entirely in the open air.

The Sontaran Experiment is a pleasing interlude between the two more substantial stories either side of it, and is memorable in its own right as an exciting and well-crafted adventure.

< The Ark in SpaceFourth DoctorGenesis of the Daleks >

This episode guide is made up of the text of The Discontinuity Guide by Paul Cornell, Martin Day and Keith Topping, and Doctor Who: The Television Companion by David J. Howe and Stephen James Walker.

The Discontinuity Guide © Paul Cornell, Martin Day and Keith Topping 1995.
Doctor Who: The Television Companion © David J Howe and Stephen James Walker 1998, 2003.

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