4 StarsUnited 93 depicts the events of September 11, 2001 from the point of view of the passengers and crew of the ill-fated eponymous flight, as well as the points of view of the various civil air and airport and military authorities. It is undoubtedly a great film, but I have reservations about naming it a classic from the first decade of the new millennium because United 93 is so different from most other films I've seen that I find it difficult to classify.The first major difference between United 93 and other disaster films (even those based on actual events) is that United 93 abandons all pretense at ordinary narrative devices. The standard grammar for a disaster film is to pick a protagonist and establish that protagonist in the ordinary course of their lives. The two police officers central to World Trade Center (also about September 11th) are established not in the ordinary course of their duties - on patrol. United 93 does not really establish its characters. In every scene, the camera is merely a fly on the wall, collecting video of events as they happen rather than depicting or explaining them. As a consequence, none of the passengers on Flight 93 are generally called by their names. They are strangers to each other, do not know each other's names, so they are rarely if ever used. There are no flashbacks to their ordinary lives to give meaning or context to their actions on the plane. They simply arrive, treat each other with courtesy, and, over the course of a few hours, band together courageously in hopes of saving their own lives and the lives of their countrymen. The same is true for the civil air authorities, airport, and military personnel. They are not introduced to the audience, simply observed by the audience going about their day in the crisis.In the opening hour of United 93, my critic brain speculated that this was possibly going to hamper the film's ultimate emotional impact, but it doesn't. The scenes of the effectively unidentified passengers calling home to tell their loved ones goodbye is heart wrenching. The cast, of mostly unknown or little known actors, is very, very good.The second difference between United 93 and other films like this is that many of the civil air, airport, and military personnel appear as themselves in the film. They are not so much portraying what happened on September 11, 2001 as they are reenacting their parts in the events of that one horrible day. In this way, Greengrass blurs his fictionalized narrative with the reality of the memories of those who were there. Again, it's incredibly effective, but I'm uncertain what its effect is.In the end, United 93 joins a list of films that are noteworthy for their uniqueness like Brokeback Mountain (unique at the time of its making for the portrayal of a homosexual romance) and 2014's Boyhood (unique because the film's narrative was filmed over twelve years following the actors as they really aged). All three films have rightly been praised for expanding the medium and being excellent. That said, the question that looms after observing unique films is: If ten films like this were made, would this be the best one? In the case of United 93, I'm not certain it would be. It's certainly a great film, but I can't say that it's the classic I've been searching for. I'll continue to look for that classic when I watch the next film for this project, Memento.