Director: Charles de Lauzirika
For, really, the hardcore Blade Runner fan, Dangerous Days (2007) tries to put the documentary treatment to much of the same ground as Paul Sammon's book, Future Noir: The Making of Blade Runner.* It's definitely its own thing, and they cover different but overlapping territories. There's participation from darn near everyone - and who knows who they left on the cutting room floor.
But, yeah, from coffee shop conversations about "you should adapt this novel" to "huh, looks like we made a cultural juggernaut", and everything inbetween, it's an expansive view of not just the vision and why's and wherefore's of this very special film, but a look at the machinery of movie-making that's only got one layer of gloss. 25 years after the fact, people are more generous with each other, even if you do wind up with conflicting versions of events here and there.
Worth it for the behind-the-scenes looks as much as the interviews, but... just know as I did not when I started the doc - it's 3.5 hours. Break it up into a 2 or more viewings. It has handy chapter sections, so feel free to turn it off and come back.
Coincidentally, this is the first book I ever purchased through Amazon.