Darkly is the key word here. Superman's vulnerabilities have nothing on those of Bob Arctor, aka Agent Fred (Keanu Reeves, plus computers), an undercover narcotics officer with a secret past and an unshakable addiction to the brain-damaging Substance D. Both cop and copout, this "ultimate everyman" might be the most fractured protagonist ever to grace an American movie: Assigned to spy and rat on his D-dropping friends, then on himself, the fried narc succumbs to his jones and eventually loses all but two brain cells, forgetting duty and identity alike. Adding insult to a psychic injury that's deep from the start, Arctor's bosses at the Orange County Police Precinct force him to conceal his true self (whatever that is) under a hi-tech "scramble suit" -- a kind of kaleidoscopic body-hologram that morphs at split-second intervals to reveal portions of men, women, and children of every variety. His corporate/government masters admiringly refer to their digitized puppet as a "vague blur"; we might call him an unreliable narrator, except that the world he's surveilling -- controlled by a shadow cabal of Halliburtonian proportions -- is more spun than he is. Even paranoids have enemies -- and only a paranoid, perhaps, can see them clearly.
Printed in 1977, the year of Star Wars and Close Encounters, Dick's counterculture postmortem -- which culminates in a list of drug-related casualties, including the author himself -- is hardly escapist sci-fi or even sci-fi at all. That futuristic scramble suit, however metaphorically vivid, mainly served as a means for the author to slide his semi-autobiographical Fear and Loathing in Orange County past the publisher at the start of the Just Say No age.
Dick wasn't one for solutions -- "There is no moral in this novel; it is not bourgeois," he writes in the book's afterword -- and neither is Linklater. There's hope in A Scanner Darkly, but only a sliver -- just the momentary spark of two tiny lights in a sea of black, or the rare gift of a filmmaker whose fixes are paradox and contradiction.