Heroin is not the cause of junkies. My God, you guys can be so dull. The characters in the movie are obviously dumb, shooting up everything they can get into their arm and working to get anything they can, it's their own fault. It's people's own stupidity that gets them into trouble like that. I'm not a user and I'm not defending users or saying Heroin use is ok. Just that's the way it works. The movie... meh.