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For a long time, most Doctor Who novelisations were based on stories longer than 4 episodes. And for a long time, only one two-part story had been novelised - The Sontaran Experiment. Ian Marter, the actor who had portrayed Harry Sullivan in the story had taken on the task of turning this story into a novel. His adaptation of the TV story proved to be the benchmark for future novelisations: thankfully most other novelisations of the shorter stories proved to be as equally well-written.

The TV story itself is quite good and stands good stead even today, although I imagine that if this particular story had been made now the robot would either be CGI or a much more convincing model. I would also be interested to know if, as in the documentary contained on the DVD (Built For War), there would be more than one Sontaran? This is the best of the Sontaran stories, narrowly beating the introduction story and between this adventure and the wonderful novelisation it makes me hope that these clone warriors will return in the not too distant future. Hint, hint, Mr Davies!

Back to this particular TV adventure - its short length means that its quite light (certainly in contrast to the two stories it bridges, The Ark in Space and Genesis of the Daleks). However, it is quite entertaining and adds some interesting layers to the Doctor Who universe - not least the reinforcement of the clone nature of the Sontarans. Its a pleasant way to pass an hour and if you can find the novelisation - read it, because it really does add to the story!