This book has been made into a film set for release in September. The movie has been directe by Richard Linklater, of Slacker and Waking Life fame, and is shot in the same style as waking life.
The plot revolves around the use of drugs and an addict who is either hallucinating that he is a narc or a narc that has become an addict. Interesting takes on drug use, addiction, and drug treatment. Philip K. Dick is one f the trippiest SF writers of the last century, and this one, written in 1977, is one of his finest works.