When Arctor is going through the second phase of testing with the medical deputies, the laptop-like machine on which he is being tested is branded as V K mk1. V K stands for Voight Kampff, the test used in “Do Androids Dream of Electric Sheep” (a.k.a. “Blade Runner”) by Philip K. Dick, where the test is used to measure the response time and the involuntary reaction of the pupil of the eye, in short, an emotional reaction to determine whether they are humans or androids.

The title is an appropriation of 1 Corinthians 13:12, which reads, in part: “For now we see through a glass darkly; but then, face to face: now I know in part; but then I shall know even as I am known.”

Robert Downey Jr. wrote most of his lines down on post-it notes and scattered them around the set so he could read off them while filming a scene. The rotoscoping team simply animated over the notes to remove them from the film during post-production.

When Arctor sits on the stage waiting to give his speech to the Brown Bear Lodge, one of the images his scramble suit displays is Philip K. Dick. This is a clever reference to the novel, in which the scramble suit is said to show the likeness of its creator once in every several million permutations.

According to director Richard Linklater, the filming of this movie was completed in 23 days; the animation process took 18 months

The filmmakers looked at 60 houses before settling on the one used for Arctor’s home.

Fred: I’d say Arctor is doomed if he’s up to something. And I have a hunch from what you’re saying that he is.

Fred: I saw death rising from the earth, from the ground itself, in one blue field.
[picks up a blue flower]
Fred: A present for my friends… at Thanksgiving.

Fred: What does a scanner see? Into the head? Into the heart? Does it see into me? Clearly? Or darkly? I hope it sees clearly because I can’t any longer see into myself. I see only murk. I hope for everyone’s sake the scanners do better, because if the scanner sees only darkly the way I do, then I’m cursed and cursed again.

Fred: [voiceover] Crazy job they gave me. But if I wasn’t doing it, someone else would be. And they might get it wrong. They might set Arctor up, plant drugs on him and collect a reward. Better it be me, despite the disadvantages. Just protecting everyone from Barris is justification in itself. What the hell am I talking about? I must be nuts. I know Bob Arctor. He’s a good person. He’s up to nothing. At least nothing too bad. In fact, he works for the Orange County Sheriff’s office covertly, which is probably why Barris is after him. But that wouldn’t explain why the Orange County Sheriff’s office is after him. Something big is definitely going down in this house. This rundown, rubble-filled house with its weed patch yard and cat box that never gets emptied. What a waste of a truly good house. So much could be done with it. A family and children could live here. It was designed for that. Such a waste. They ought to confiscate it and put it to better use. I’m supposed to act like they aren’t here. Assuming there’s a “they” at all. It may just be my imagination. Whatever it is that’s watching, it’s not human, unlike little dark eyed Donna. It doesn’t ever blink. What does a scanner see? Into the head? Down into the heart? Does it see into me, into us? Clearly or darkly? I hope it sees clearly, because I can’t any longer see into myself. I see only murk. I hope for everyone’s sake the scanners do better. Because if the scanner sees only darkly, the way I do, then I’m cursed and cursed again. I’ll only wind up dead this way, knowing very little, and getting that little fragment wrong too.

Fred: Whatever it is that’s watching… it isn’t human.

Bob Arctor: The pain, so unexpected and undeserved had for some reason cleared away the cobwebs. I realized I didn’t hate the cabinet door, I hated my life… My house, my family, my backyard, my power mower. Nothing would ever change; nothing new could ever be expected. It had to end, and it did. now in the dark world where I dwell, ugly things, and surprising things, and sometimes little wondrous things, spill out in me constantly, and I can count on nothing.