I watched this film purely because Chiwetel Ejiofor stars. Ejiofor's performance in "Dirty Pretty Things" was superb and I have been keen to see another silky, powerful performance from him. Sadly, many of his more recent efforts, while achieving commercial success, have not shown off his acting chops. Thankfully, Redbelt does. Redbelt is a very accomplished film. If I have a criticism, I would say that it is not particularly "cinematic." However, that is not to say that you shouldn't seek it out. If you like David Mamet's gritty cop shows, this has a similar feel and multi-layered storyline.
The film deals with the fundamental tenets of all true martial arts and compares them to the temptations of big business - here, movies, pro MMA fights and to an extent, fashion. Ejiofor's character is a warrior, but the story is about finding a way to prevail in seemingly impossible circumstances, the whole time struggling to maintain his integrity, and that of the art he has dedicated himself to. Not all of his fights are physical and this is where the film scores for me. While some other reviewers have criticised the story for lacking credibility, I felt that the story more than carried itself. All effects had a plausible cause and the snowballing problems could be real enough.
Additionally, those who have criticised the fights might be well versed in chop socky films (nothing wrong with that!), but Redbelt does a fine job of showing off Jiu Jitsu. Moreover, Ejiofor's fights are far more entertaining than anything I have seen from Steven Siegal - a bona fide Jiu Jitsu martial artist. Jiu Jitsu doesn't have the "wow!" factor of kung fu, but if you appreciate the skill of close quarters grappling, Redbelt has some excellent scenes.
While many Hong Kong Kung Fu films from the past tried to communicate the principles of martial arts, few survived the translation process. The stripped back approach Mamet has chosen for Redbelt, along with the West Coast setting, really help to put the principles into a setting that will be easier to understand for Western audiences. Although there were some highly predictable set pieces to the film, I would say that it represents it genre very well.