Kathryn Bigelow, director of the Oscar winning The Hurt Locker, returns to the war on terror with this high-octane, true-story account of the hunt for Osama Bin Laden.

Before the movie begins, a heading announces that this story is based on true events, from first hand accounts. From that point on it balances on a knife-edge between documentary and drama. It is a strange sensation, watching a film that feels so much like an action movie, but depicts true events that only happened a few years ago. The film is undeniably entertaining, and the action scenes thrilling, but it can’t help but feel like a learning experience at the same time.

The movie opens with a blank screen, and then the audio begins. In my screening, the audience was silenced as the tragic events of the 11^th of September 2001 were recounted through telephone calls from those on the planes and inside the World Trade Centre. Then the movie began, following every step of the 10-year search for the Al-Qaeda leader.

This story is really about the obsession of one woman, CIA operative Maya (Jessica Chastain). This fiery intelligence agent uncovers a lead and refuses to let it go, her conviction overpowering the doubts of many of her colleagues and superiors. Chastain is convincing in this role, delivering an engaging and passionate performance. However, while The Hurt Locker was a brilliant depiction of how war affects the psychology and humanity of those involved, Zero Dark Thirty did not delve so deeply into the human psyche  – there are few emotional moments for Chastain to get to grips with, although she handles each one she is given excellently.

A lot of the story runs along the lines of a political thriller; for the most part this is an investigation, not an assault. The tense operations will have you on the edge of your seat, even though you already know the outcome (spoiler alert: we got him). However, there are plenty of moments of action – shoot-outs and explosions abound. The climax of the film is riveting. As US Navy SEAL Team Six fly towards Osama’s compound, in a helicopter they could have borrowed from Batman, you watch the whole assault unfold as if you were a member of the team itself.

Bigelow has received criticism for her depiction of torture in the film; the first hour or so focuses closely on the “enhanced interrogation techniques” used on detainees at secret CIA “black sites”. Critics have claimed that the film is endorsing torture, as key information is acquired through this controversial method.

However, although the depiction of these events is uncompromising, it is in no way glorifying. The CIA operatives involved show no pleasure in their actions, and even demonstrate a degree of revulsion at what they do. The filmmakers have simply portrayed events as they understand them to have happened. While some viewers may find these scenes disturbing, they are not particularly graphic and should not cause undue offence.

To some it up, Zero Dark Thirty (military jargon for 12.30am, in case you were wondering) is a gripping, dramatic and entertaining portrayal of the War on Terror. Treading similar water to popular television show Homeland, the movie already has audiences excited and, with five Oscar nominations, looks set to replicate the success of The Hurt Locker.