The Sontaran Experiment written by Bob Baker & Dave Martin and directed by Rodney Bennett

This story in a nutshell: The title couldn’t make it much clearer…

Teeth and Curls: Maybe it is because it is all filmed on location or maybe because it was one of the first stories filmed but there is a sense of nervousness about Tom Baker’s performance in this story that we would never see again (not even in Robot did he appear quite this tentative, aside from some uncertainty in Revenge of the Cybermen, but that might be the quality of the material). He’s quiet and subdued for the most part with only the odd flicker of dominance and wit in the first episode. He finds his way come episode two but for a long while this feels like a Doctor Who story with a missing protagonists, more concerned with showing off the pretty scenery than pandering to the main man. When he says he has lost his sonic screwdriver and feels lost without it there is a hesitation in his voice as though he doesn’t know how far he can push the eccentricity of the part yet. The Doctor takes the piss out of Harry’s ability to fall down a ‘whacking great subsidence’ and then does so himself. Thinking about it come his penultimate season he is as bumbling and as accident prone as Dr Sullivan, and it is probably good that they did not travel together at that point in his life. Imagine the catastrophic consequences to the universe. The moment it all seems to click into place for the 4th Doctor is when he is confronting Styre and challenging him to a duel to the death, Baker relishing the chance to square up to his opponent at last and the stuntman who took his place during much of the fight giving his Doctor a real sense of formidable violence. This is certainly not a story I would stick on to watch Baker at the height of his powers. Strangely enough that would be the next story.

Lovely Lis: Everybody else lands on their feet but poor Sarah materialises in the bushes with her arse in the air. You've got to love her, haven't you? Sarah told Mike Yates that she liked London exactly the way it was in Invasion of the Dinosaurs and here she gets a close up view of exactly what they were trying to achieve with Operation Golden Age and it really throws her. The silence is disquieting, she enjoyed the hustle and bustle of the Capital City. This isn’t what she expected for the future of her planet. She has clearly been travelling with the Doctor for enough time now so that she has come to expect mutations and creatures…she’s on the right track and only has to wait until the next story for her fears to come true. The mental torture that Sarah is put through is pretty strong stuff for a family audience, whilst the snake is clearly a Pound Shop special the zooming close ups of the rocks and the adhesive sludge crawling up her legs are both really nasty moments that would test the character of anyone placed in those circumstances. The Sontaran Experiment is proof that I could watch Sarah and Harry arsing about doing anything, they don't exactly get their most sparkling material but the mix of personalities makes their scenes together sing.

Dashing Doctor: Harry is such an old fashioned romantic sort and he can’t resist running to Sarah’s rescue and calling her ‘old thing.’ Ian Marter brought a great deal of charm to the funless, violent stories of season twelve, so appealing that it is a crying shame that he only appeared in seven stories. He's a medical man through and through and finding a victim chained to a rock and deprived of water makes his blood boil. When he dies before he can help him, Harry heads off to deal with the stinking little toad that is responsible. Not that I wish to question his medical competence but if Harry had given Sarah and the Doctor a thorough examination he would have realised they were both still alive. Just saying. Who cares though when he very sweetly decides to avenge their deaths by going after Styre with a bloody great plank of wood? He clearly has a great deal of affection for both of them.

Sparkling Dialogue: ‘Why did you make that disagreeable noise?’ – says Styre of Sarah’s scream. At the time that I originally watched this I was embarking on a Doctor Who marathon with my husband – he finally asked me to walk him through the entire run of the series, one episode a night. We were about two episodes into The Daleks when he kept asking the same question as Styre, usually about Susan.

The Good Stuff: An all location story is such a brave idea for the time of challenged budgets and Philip Hinchcliffe cleverly avoids problems by having a six parter split into two stories with four episodes all studio and two episodes all OB. He’s already proving himself to be a very savvy producer. He would later pull off a similar innovation in The Deadly Assassin by confining all the location work to one, startling episode. The slow pan across the bleak moorland tells a bleak story about the future of the Earth that the Doctor and friends are visiting. Sarah’s haunted reaction to the Earth being nothing but soulless moorland and the revelation that they are standing in Central London is one of those moments of Doctor Who cheek that genuinely gets away with it. Clearly it is just a empty landscape that the production team have stumbled across to shoot this story in but if you allow yourself to believe that this is the re-grown landscape after the Earth has been sterilized by fire suddenly the landscape becomes a story in itself. That is the magic of Doctor Who, conjuring up enough evidence to make you believe. Harry slipping down the ravine is a great stunt because it looks entirely accidental and dangerous, not an easy thing to pull off. The more time you spend on this location the more you understand why it was chosen; miles of desolate greenery, mountainous hillocks and interconnected rockeries. It's British countryside at its finest and the silence is deafening. I love the moments when people are spotted just out of sight – it is filmed so quickly you are left thinking ‘did I just see that?’ Death to the Daleks pulled off a similar trick. It’s in those moments that the atmosphere of the first episode really works. I like the fact that the Galsec chaps are scruffy and violent; it is a sharp contrast to the emotionless and sterile populace we discovered on Nerva Beacon.  Setting a story on the Ark with the sleeping remnants of humanity and then opening out the same universe to a story set on the Earth with a militaristic survival group paints an epic picture of this time period that Doctor Who doesn't usually go to the effort of realising this well. Normally this sort of thing is usually only mentioned in dialogue to save money but here we actually get to see this period from two very different perspectives. The End of the World/New Earth/Gridlock would pull off a similar trick in many years to come. The Sontaran ship looks wonderful nestled amongst the rocks; it is a defining visual image from this story. Everything about the cliffhanger is excellent from the dramatically rising music, the long awaited appearance of the Sontaran and Sarah’s shocked reaction. This is the first of two stories in a row where Sarah will be reunited with old foes and her reaction is a beauty. Styre is another fine Sontaran character with a delicious sadistic edge. You get the impression he enjoys the more intimate one on one torture (sorry, experimentation) than simply fighting a large scale war. The mission on the Earth to see if it is a viable base gives the Sontaran/Rutan army a real sense of magnitude, gathering entire worlds to play their game of war across. Having Kevin Lindsay play both Sontaran characters really stresses the fact that these creatures are clones. Styre shoots the Doctor and doesn't even bother to dispose of the corpse, treating the leading man as so much garbage. It is probably the least arresting for children (especially when compared to snakes and slime) but easily the most agonising experiment when given any degree of thought, the breast cage test of strength (two men holding a metal weight that is slowly getting heavier over the the chest of a man tied down, threatening to crush in his rib cage) makes my eyes water just to think about it. Watching the two men struggling to save the life of their leader who has betrayed them shows a real sense of character. It is very unusual for Doctor Who to have an entirely physical conclusion with no dialogue (because it is often the cheapest way to tell a story) but the fight between the Doctor and Styre is absolutely spectacular. They dash over those rocks, the camera enjoys the full scope of the scenery and the fight arrangement is full of energy and class.

The Bad Stuff: This is one occasion where I feel that the story deserved to be shot of film and not video so ironically it’s the one of the few occasions pre-Trial of a Time Lord where it isn’t. It would look so much more lush and expensive on film and instead there are times when it feels as if somebody has taken a camcorder and a group of friends to Dartmoor to film a fan production (it looks a lot like one of the Myth Makers tapes at times). It doesn’t help that the guns the soldiers carry and the robot look pretty tacky too, as though said fans have cobbled them up out of things in a kitchen cupboard. The funny business with Harry landing and vanishing probably looked better on paper than it does in practice ('are you coming or going?'). The shots of the robot and the guy running in the same frame are very funny (and I don’t think that was the intention) – it almost looks like a spoof of Doctor Who. When Sarah says that Styre is identical to Linx she is being quite kind to the designer because aside from the shape of the creature the mask looks completely different.

The Shallow Bit: Lis Sladen looks adorable in her bright yellow raincoat and woolly hat. Mind you Lis Sladen often looked adorable in anything.

Result: Unique at the time for only being two episodes long and shot entirely on location, The Sontaran Experiment is a pleasant breather after the stifling claustrophobia of The Ark in Space and a pause before the horrors of Genesis of the Daleks. I really wish this had been shot on film because video does make the location work look cheaper than it should. However the scenery is so spectacular it manages to get away with the awesome premise of being set on a post apocalyptic Earth, the planet having survived a battering by solar flares. Because of its brevity, this story is more effective as a coda for the story that took place before it than a gripping narrative in its own right, and also as a further glimpse at the Sontarans and emphasising their terrible war with the Rutans. Tom Baker seems a little tentative at first but soon finds his way and luckily he is backed up with the unconquerable team of Lis Sladen and Ian Marter who keep things ticking over nicely. Rather than the often cosy violence of the Barry Letts era, much of the material is quite sadistic and already the new administration is making its mark. I watch this story for its gorgeous windy locations, which makes me want to walk across South Downs where I live and breathe in some lovely fresh air. As a story with its own identity it is fairly disposable, but this is still an enjoyable enough tale that adds extra depth to the corner of the galaxy set up in The Ark in Space: 7/10