A History of Violence is one of those movies at which you spend most of your time completely clueless about what the hell is going on. But in a good way.

After a summer of remakes and bad comic-book adaptations (God have mercy, Ioan Gruffudd opposite Jessica Alba?!), I enjoyed seeing a movie that demanded that you actually pay attention. Nope, no text messaging, no making out with your significant other, and no burying your face in your super-sized popcorn. The movie opens with a long shot of an off-center lawn chair leaning up against a shabby-looking building while cicadas drone in the background. Anything this seemingly boring should quickly clue you into the fact that you won't be able to set your brain on cruise control.

Viggo Mortensen starts in this thriller directed by the same man responsible for both The Fly and the movie adaptation of M. Butterfly. He plays Tom Stall, the average-Joe owner of a small Midwestern diner, a respected citizen, a devoted husband to Maria Bello, and a perfect father to two children. He drives a Chevy. He picks up trash on his way to work.

This idyllic existence begins to fall apart when two violent criminals walk into his diner. Faced with the possibility of them shooting his waitress and everyone else in the room, Stall jumps the counter and gruesomely dispatches of the bad guys. He quickly becomes the hero of the small town, and, not surprisingly, draws reporters like buzzards to road kill.

Enter Ed Harris, in a nice turn as a mobster from Philly. He's quite creepy as he lurks around the movie in a black luxury vehicle (there is some serious Cadillac product placement going on in this movie - and always with mobsters sitting in the cars). He's looking for someone that he thinks Tom Stall could be: a killer for the mob.

Is Tom the killer or the good guy? Maria Bello's character, Edie, begins to wonder. Meanwhile, violence starts to creep into every aspect of their lives. Characters that would have taken the high road at the beginning of the movie begin to solve problems by lashing out with their fists. By the time the movie lets us know who Tom really is, the distinction between good guys and bad guys has crumbled in the face of the powerful, all-consuming influence of violence.

And the violence here is particularly gory and shocking. Unlike your usual pop-pop, the bad guy's dead, isn't this a cool movie? violence, the director seems to make a point of disturbing the audience. Rather than getting a voyeuristic thrill out of watching Steven Segal kick the crap out of a bunch of guys, the audience has to watch a man's jawbone still working in the bloody remains of his blown-off face. The noises of the guns aren't clean and muted; they're loud, and you can practically feel the recoil. While this is all reminiscent of Sin City, the gore proves to be much more disconcerting when portrayed in living color, set in small-town America.

Between the violence and the sex scenes, this movie certainly earned its R rating. The two sex scenes, while thematically important and emotionally charged, are explicit. Let's just say that Viggo has some talents not brought to bear in Lord of the Rings. If they had been, Christopher Tolkien probably would have assassinated Peter Jackson in his father's memory.

Of course, Viggo Mortensen also displays his talents as a first-rate character actor in the role of Tom Stall. While I don't want to give too much plot away, Mortensen essentially plays two vastly different characters. He pulls them both off convincingly, while also unifying them into one man. Maria Bello, in a role that could have been reduced to a cardboard stand-up of a character, instead comes across as a justifiably confused and horrified wife who finds herself unsure of her husband's identity.

At times, I found myself equally unsure of how exactly to react to the movie. Sometimes it can be suddenly funny in inappropriate moments. Tom Stall is a complete riddle, as is his wife, Edie. Often, you can't predict exactly what a character will do next. The resolution remains unclear until the very end of the movie.

I suspect this refusal to clarify everything for the audience is on purpose, however. What can you do about your history of violence? Can you start over? Can you escape your past? Is it possible to avoid violence at all? There are moments when characters find themselves forced into using violence. What other decision could they have made?

What's clear at the end of the movie is that you can't simply ignore your own past. This theme is particularly interesting in light of the movie's portrayal of a small American town invaded by big-city crime. Americans have created a national legend for themselves which is deeply tied up in men like Tom Stall. We tell ourselves that we believe in small business, family values, good citizenship, and standing up for yourself. What happens when your history of violence catches up to you? Well, it certainly isn't pretty.