RU Sirius Show interviews Richard Linklater

The RU Sirius Show celebrates its first birthday party with an
interview
with Richard Linklater
about A Scanner Darkly.

Linklater: … substance D. I mean, what kind of drug is it? I remember
in the seventies … everybody was saying, you know, there needs to be
a designer drug that isn't harmful, isn't addictive and yet allows
the user to kind of transcend … the reason people do drugs and do
alcohol is that people have to kind of transcend themselves and alter
time. The human psyche sort of requires that. So instead of that
utopian notion and that healthy notion of what that drug would be I
thought of just the opposite. Substance D is a drug that is
immediately addictive and expensive enough so that you have to work
and it's profitable to whoever is selling or making it. And also,
more sinister (laughs), you lose yourself and yet you're still alive
and kind of able to be slave labor. So it's your most paranoid drug
you could imagine. The effects are somewhat euphoric but it's mainly
its addictiveness that I thought was the key. Because if you really
could do a drug that was immediately addictive as Robert Downey Jr.
describes in the movie…

I worked a lot of this out with Robert, actually. He contributed
heavily to it… as he'll jokingly say he did 20 years of research into
this very subject…

He contributed that line, "You're either on it or you haven't tried
it when we're talking about the D. There's no weekend warriors on the
D."

Link