Filmed in a unique animated style, A Scanner Darkly opens with dozens of insects crawling over a disheveled man named Freck (Rory Cochrane). Freck scratches and shakes himself, jumps into the shower and does everything he can to get rid of them, but to no avail. Even his dog is infested. Freck later realizes the bugs never existed; rather they were a side effect of the drug Substance D.

Set in the not-too-distant future where American has lost its “war” on drugs, “A Scanner Darkly” centers on undercover cop Fred (Keanu Reeves), who is one of many people hooked on the popular drug Substance D, which causes its users to develop split personalities. Fred is obsessed with taking down Bob, a notorious drug dealer, but due to his Substance D addiction, he does not know that he is also Bob.

The movie was filmed digitally, and cell animation was traced over it. It is reported that each minute of animation required hundreds of hours of work. The most eye-catching moment is the first time you’re introduced to Fred, who wears a special suit that constantly morphs into various people so he can’t be identified (think Michael Jackson’s music video “Black and White,” only in animation).

You feel uncomfortable from the start of the film, watching the messed-up Freck interact with his supplier Jim (Robert Downey Jr.), who has no problem getting Freck more and more hooked on Substance D. Downey Jr. does a good job of playing an apathetic drug dealer, who playfully swings around his gun and at one point idly watches as a roommate nearly chokes to death.

The only halfway likeable characters are Bob and Donna (Winona Ryder), who share drugs but not each other. Their relationship is never truly developed until the last 10 minutes of the film, and you wonder whether it may have been better to introduce their complex relationship earlier in the story to give it more depth.

The most interesting part of the movie is the end … if you didn’t figure it out ahead of time. Fred’s gig is up, and he learns his fate. You also find out where Jim, Freck and Donna wind up. The film has an anti-drug message, but it doesn’t delve deep enough into the dirty and dangerous repercussions of drug use. While the film makes its point, it’s a slow 100-minute journey that doesn’t really get you hooked.