I did not expect to enjoy this as much as I actually did. With its length, complicated nature and incredible detail Zero Dark Thirty was a fantastic piece of work. Jessica Chastain was brilliant in the convincing centre piece of the narrative. It was long, starting strong, losing credit towards the middle but the final hour was terrific. Right down to the raid which was full of suspense and drama. Like the raid itself, it was a precise and scintillating piece of cinema. In the end it felt worth it, I have little interest in the context of its accuracies of the actual events, nor its controversy. In the scheme of things I watched for entertainment, and it delivered. If you're in the mood for something dramatic with a serious tone, watch Zero Dark Thirty.

Maya, a tenacious CIA agent (Jessica Chastain) searches for world's most wanted man: Osama Bin Laden, against the background of terrorist attacks against Western targets. Director Kathryn Bigelow does a masterful job of blending tension and action with the sometimes tedious processes of data analysis and surveillance (the film compresses eight years of searching for the 9-11 mastermind into 160 minutes). Chastain is excellent as the driven analyst and the film wisely wastes no time on her life outside the search (i.e. no gratuitous romance, personal affairs, etc). The rest of the cast is also quite good, especially Jennifer Ehle as Maya's colleague Jessica. The lengthy climatic set-piece, as the special-ops team move in on bin Laden's compound near Abbottabad, Pakistan is outstanding. The film was controversial for its depiction of torture (aka 'enhanced interrogation techniques') as an effective 'necessary evil' in the 'war on terrorism'. 'Ends vs. means' arguments aside, 'Zero Dark Thirty' is a riveting adventure with some great action sequences, but I admit that I have a very non-PC love for films like this and that some people might find the film repugnant (especially the first half-hour).

Zero Dark Thirty is a procedural CIA-based thriller in the mould of TV's Homeland. This film, however, is based on real-life events, so it doesn't have the benefit of being able to withhold in the way Homeland's first series did with Twin Peaks-like delectation. What Zero Dark Thirty does have is a narrative based on first-hand accounts, and it makes no explicit judgement about the content of those accounts. We simply get to see what (apparently) happened during the manhunt for "UBJ".

The film's lack of polemic is both a blessing a curse. It's a blessing because it's rare that a film dealing with such volatile subject matter is depicted procedurally. Usually when a narrative is made ostensibly apolitical it's as a result of an unconvincing moral rebalancing, where the filmmakers go to great lengths to present both sides fairly. But Mark Boal and Kathryn Bigelow's disinterest is also a curse because, in avoiding judgement, it surreptitiously falls firmly on the side of the CIA. It shows what it's allowed to show, but keeps their secrets ("undisclosed location" and all that); and it portrays the operatives as the honourable front-liners getting their hands dirty (but not bloody), beyond moral reproach by virtue of hard graft. In Bigelow's world, it's the suits in Washington who have the blood in their hands - they're disconnected, as evidenced when torture-specialist Dan (Jason Clarke) returns to US headquarters from the field and loses his nerve, becoming a man of soft probabilities.

Clarke is solid but lost amidst superior talent, as he was in John Hillcoat's recent Lawless. Jessica Chastain delivers a nuanced performance. Driven professionals in films often come across as stolid, but Chastain is an actor of subtlety - even if Bigelow can't help lensing her like a wind-swept movie star in the Middle Eastern magic light. Jennifer Ehle uses her moon-faced radiance to good effect, filling her eager operative Jessica with youthful energy. There's a fair amount of distracting spot-the-cameo going on, particularly toward the end, when Joel Edgerton, Mark Duplass and James Gandolfini turn up.

Bigelow's directorial talent is never in doubt. The final sequence in particular is harrowingly tense, even though we know the outcome. And she generally gets the best out of actors. But make no mistake: this is a deeply patriotic film which is cheering for the home team, and it does so under the guise of objectivity, which makes it more manipulative than flag-waving fare like Last Ounce of Courage or Act of Valor, albeit much more skilfully made.