The episode kicks with a thrilling pre-titles sequence that contains the much-vaunted reappearance of the Cybermen. After a string of great performances this year, it's nice to see Arthur Darvill's Rory (aka the 'Lone Centurion') take centre stage here, and though some might be disappointed to see The Doctor's second-most popular foes given such short shrift, their appearance lends this instalment a truly epic feel.
However, one of the great things about Doctor Who has always been how it examines the grand and the fantastical through human (or at least humanoid) eyes, and here the CGI spectacle and galaxy-trotting are grounded by a number of engaging and emotive performances. Christina Chong is particularly good as Lorna, the little girl who The Doctor left behind, and her death scene is one of the episode's more touching moments.
Less well-handled is Neve McIntosh's return as new character Madame Vastra. Her performance itself is not at fault, but the notion of a crime-fighting Silurian cutting down serial killers in Victorian London seems a rather random idea to throw into a finale that's already bursting at the seams, while her implied relationship with the under-written Jenny (Catrin Stewart) is basically just an excuse for a few cheeky gags. When it comes to the villains, the only one to make a real impact is 'that eye-patch woman' - Madame Kovarian. Frances Barber isn't given a great deal to do, but delivers an entertainingly arch performance, and it's certain that we'll see her character again. As a side threat, the headless monks are a bit limp, if only because their purpose and origins are never really explained.
One of the most interesting aspects of 'A Good Man Goes To War' is the attempt it makes to question The Doctor's actions. It's certainly a bold move to point out the inherent flaws in the character's persona, but it begs the question, where do we go from here? It's all very well to criticise The Doctor for his increasingly violent ways, but ultimately the character's attempts at peace have to fail, and he has to battle the monsters. Otherwise, we're left with a very dull show indeed. Nonetheless, as events begin to spiral out of control for the overconfident Time Lord, the episode does well in slowly building a sense of impending dread.
'A Good Man Goes To War' is not without its flaws, but it is still a terrific 50 minutes of entertainment. There's the odd plot oddity here and the occasional lack of clarity there, but ultimately this mid-series finale is thrilling, shocking and the cast give it their all. It's important here to give one last shout out to the main man, Matt Smith, who has truly excelled himself in these seven episodes. His performance displays a fantastic range and constant surprises. As for Who head honcho Steven Moffat, it's clear that he's going to be spinning this particular yarn for a little while longer yet, but enough answers have been provided for now to keep this reviewer satisfied (just about). Now… what's all this about Hitler?