As someone who enjoyed the visually unique and philosophically-inclined Waking Life, as well as many film adaptations of the work of Philip K. Dick, I had been looking forward to A Scanner Darkly.  However, I actually knew very little about the plot before going in, and I think that my unfounded expectations tainted my enjoyment of this film.

I had been expecting some dystopian future piece (of which I am very fond of) due to the fact that almost all of Dick's work has that theme.  While an argument could be made that A Scanner Darkly is such a piece, it's really more a film about drug culture, and the war on drugs.

Keanu Reeves is Bob Arctor, an undercover cop attempting to find out the origins of the latest, deadliest street drug - Death.  However, in infiltrating the social circles of the hopelessly addicted, Arctor finds he has to consistently take the pills himself.  Needless to say it's a rapidly deteriorating slippery slope for the protagonist.

Despite the fairly depressing plot, the film itself is quite humorous.  This is due to the supporting actors, Robert Downey Jr., Woody Harrelson, and Rory Cochrane.  As Arctor's wastoid friends they each represent a different aspect of the stereotypical druggy - insanity, paranoia, and mindlessness.  Honestly, I think the genre that this film does best is that of comedy.

What makes this film and Linklater's first animated piece - Waking Life - so incredible is the method in which it's animated.  First the entire movie is filmed, using real actors and real film.  Then artists actually use that film and sort of trace over it, giving it a surreal cel-shaded quality.  Unlike Waking Life, however, this movie has a consistent artistic style (since it's also a consistent narrative).

This visual effect is truly striking and unique, and is reason enough to see this movie on its own.  It also allows visual effects to be done simply but superbly, such as the cloaks the undercover cops wear while not undercover - a constantly shifting sea of clothing and facial features used to hide who they are from the other undercover cops.

So, if you're able to enjoy a film on a purely visual level, then this movie is certainly a must.  If you could care less about the visuals, then this movie is certainly entertaining, but the points it's trying to make about the war on drugs and the system don't carry this movie.  If anything carries this film, it's the top-notch supporting actors.  Worth a watch, but don't go too far out of your way to see this one.