The ends of the book and movie versions of "A Scanner Darkly" list people author Philip K. Dick knew who suffered illnesses due to long-term drug use, and Dick himself is on the list.
Indeed, as wiki explains, Dick had a long history of amphetamine use and even shared a house with other addicts -- experience that no doubt helped him write about the cranked-up addict roommates in "A Scanner Darkly" with such realistic description and dialogue.
With that in mind, I've always wondered -- did any of the main characters in "A Scanner Darkly" resemble Philip K. Dick himself? In other words, did he write himself into his story?
(The movie had five main characters: Keanu Reeves as relatively straight-edge Bob Arctor/Fred/Bruce. Robert Downey, Jr. as fast-talking schemer James Barris. Woody Harrelson as lunky stoner Ernie Luckman. Rory Cochrane as burned-out geek Charles Freck. Winona Ryder as shady cokehead Donna Hawthorne/Audrey/Hank.)