A disturbing and emotionally cathartic account of the hijacking of the fourth of the 9/11 planes. Told with great verve we follow the stories of both the abductors and their captives and the chaos in the civilian and military air-control rooms. While the terrible truth dawns on the passengers, those on the ground watch helplessly as the terrible events of the day unfold. As for political comment, Brit director Paul Greengrass makes no overt judgement; we just observe an initial reaction amongst the military that this might be a computer simulation and the utter and total frustration in both control rooms at their inability to contact anybody in authority, either military or civilian, during the entire time of the attack.