The one thing this story did fantastically was the thing it substantially set out to accomplish: to re-introduce the Sontarans. I would confidently say this story was the Sontarans’ best, in the sense that the Sontarans were portrayed the best. This story was hugely successful in re-introducing the Sontarans, perfectly encapsulating what they were and what they were about: a race of clone soldiers who glory in war and violence. The Sontarans in this story were intimidating and fearsome, as well as somewhat comical, but not in such a way that detracted from their menace. I wasn’t as impressed with the story on the whole. The plot, concerning the mystery of the Sontarans’ uncharacteristically reticent invasion of Earth, was fleetingly interesting, but not so interesting to keep me gripped for the full ninety minutes of this fairly run-of-the-mill alien invasion runaround story. “Aliens are invading (21st Century) Earth” has become such a hackneyed trope in modern Doctor Who that stories employing the formula are invariably wont to be repetitive and tiresome. This one is no exception. As far as alien invasion runarounds go, it doesn’t particularly stand out: swap the Sontarans with any hostile alien species and one would scarcely be able to tell the difference.
Apart from the effective deployment of the Sontarans themselves, the only thing that redeemed this story was the characters—specifically Martha and Donna. Donna continues to endear herself the audience, showing what a very complex person she really is under that bluster and snark. She showed her insecurities about travelling with the Doctor in her dialogue with Martha, her concern for protecting her family, particularly her loving grandad, Wilf, from being hurt by her association with the Doctor. Although she’s not my favourite, Donna showed herself to be a unique companion in other ways: she’s not the perfect Mary-Sue that Rose and Martha were, she was petrified when the Doctor asked her to sneak through the Sontaran ship and activate the teleport pods. In a way that certainly makes her a far more relateable companion that Rose or Martha were, who both proved themselves to be extraordinary people. Although Martha spent the majority of the story locked in a basement while her clone gallivanted around pretending to be her, the little screentime real Martha got was wonderful, such as the touching dialogue between Martha and her clone. Wilf was also excellent. He’s becoming a really strong character in his own right, and easily the best friend-and-family-of-companion character we’ve had yet. One can’t help but think he’s inadvertently sending his granddaughter into danger so he can live vicariously through her…
The Doctor was good in this story, although the material he was given in the script didn’t exactly lend itself to a display of Tennant’s acting abilities. I did, however, find the Doctor a little too sanctimonious in this story—not only his frankly prejudiced aversion to soldiers (from an organisation he used to work for, no less), but his insistence on sacrificing himself at the end to “give them a choice”. How more idiotically pious could you get? The Doctor’s moralism is a central part of his character, but sometimes it goes overboard, as here. The Doctor would have known that there was approximately zero chance of the Sontarans’ backing down, so he was essentially knowingly embarking on an unnecessary suicide mission. Just not good writing, I think. I did, however, like the way the Doctor was shown to callously “use” Donna, putting her into danger for his own ends. That’s the morally-questionable-and-sometimes-outright-Machiavellian-but-essentially-good Doctor I know.
Some final thoughts: I thought Luke Rattigan was a really well-written character. He was a tragic villain in many respects. His motivations and objectives were so unforgivably selfish, but yet you can’t help feeling sorry for the snotty little oik, who was driven to make a terrible pact with the Sontarans out of resentment and grievance at the way the unappreciative world had treated him and his obviously vast genius. I hated the little git, but I also, in spite of myself, sympathised with him. That’s testament to very able acting on the part of Ryan Sampson, in any case. I thought UNIT were poorly portrayed in this story. They seem to have gone from being the beneficial and equal alliance of military and science for common endeavour that they were in the classic series to being a substantially militarist affair in this story. Finally, I thought the Doctor’s whipping up of the atmosphere converter to dispel the Sontarans’ poison gas could have been better explained; it looked like the Doctor just cobbled together a few bits and pieces from Rattigan’s laboratory that just happened to be the right components he needed.