After years of having his unique sci-fi plots Cruised and Schwarzenegger-ized for big bucks, the really dark and disturbing side of Philip K. Dick has finally found the spotlight.

There’s probably no way A Scanner Darkly would have ever made it to theatres if it weren’t for the success of Blade Runner, Minority Report, Total Recall, Paycheck, and the dozens of derivatives made possible by such big screen fare. Part of Dick’s appeal is that his paranoid dystopias seem disturbingly more possible every year, making him seem like a kind of drug-addled Nostradamus. Now, our imaginings of what the future looks like tend to be filled with images of the murky, crowded cities, menacing clones, robots and flying cars of Blade Runner. Dick was either far ahead of his time, or an unwitting architect of future pop-culture iconography.

But the real reason for the massive success of his work has little to do with his prescient philosophy: it’s the fact that he built his stories around basic, heroic characters and clever plot twists. Though he probably never intended them as such, some of his writings have yielded movie-friendly formulas that have made his ideas accessible and saleable to a wide audience.

True to form, A Scanner Darkly does feature an unpredictable turn of events, but the story lacks the sci-fi gee-whiz factor of Dick’s more detailed and ambitious futuristic scenarios. Instead, it focuses primarily on a set of characters—the denizens of a dreary California drug culture anesthetized by an addictive psychedelic known as Substance D (aka “Slow Death”) and the police who keep watch on them with NSA-like spying methods. It all seems fairly contemporary and feasible, and that’s depressing indeed.

Fans of Dick’s books are already used to heady, psychosis-drenched stories that are short on plot and long on intense, brooding characters; however, when his writing transitions from page to screen, this trait is usually watered down. Because the bulk of Scanner is Dick at his darkest, there’s little in its film translation that will appeal to the multiplex multitudes, save for the presence of big names like Keanu Reeves, Robert Downey Jr., Winona Ryder and Woody Harrelson.

Still, the film’s commercial potential is bound to be buoyed by its cast’s strong performances. The usually inanimate Reeves is surprisingly effective as the story’s unreliable narrator: the laconic, stoned drug dealer/narc Bob Arctor, played as sort of a morose mirror-image of Reeves’ blithely fucked-up Ted from Bill & Ted’s Excellent Adventure. The rest of the cast consists primarily of Arctor’s crazed drug buddies: Downey Jr., deep in his element as the fast-talking, brainy and weirdly nefarious Barris; Harrelson, seemingly playing himself as Luckman, a blissfully burnt-out hippie; and Ryder as Arctor’s foxy drug-dealer girlfriend Donna, who leads him on but then won’t let him touch her.

The film does have a unique gimmick: an animation technique known as rotoscoping, which director Richard Linklater employed previously in his philosophically rambling treatise Waking Life. To achieve this effect, his crew filmed the live actors, and then digitally traced the actual frames of the film, producing an animated style that’s strangely realistic. This technique helps create a volatile and unsettling atmosphere; in this case, it was the perfect device for a story in which all of the characters’ perceptions are warped by drugs.

It’s also an effective way to portray the cops’ “scramble suits”—devices that obscure identity by projecting onto the exterior of the suit a parade of characters that change so fast, it creates a blur. This anonymity is crucial to the weirdly contrived plot, because, for it to work, the narcs can’t know what their fellow officers look like—which leads to Arctor being assigned a gig spying on himself. Because Substance D causes the two sides of the brain to split into two separate and conflicting consciousnesses, Arctor gradually forgets he’s monitoring himself. Unfortunately, the scramble suit has to be one of Dick’s weakest and most forced plot devices. In both the book and the movie, the suits are a ridiculous concept: Couldn’t the cops achieve the same anonymity simply by having everyone wear the same mask? Another weakness the film and the book share is that the audience never gets a sense of the supposed euphoria the drug creates, so it’s hard to imagine why anyone would want to take it.

The masses might not care, but Dick’s fans will be happy that A Scanner Darkly shows remarkable fidelity to the source—right down to the exact use of some of the dialogue. The book, originally published in 1977, takes place in 1994—what was then a near future. The movie does a similar short jump forward in time, updating Dick’s writing with witty, well-placed references (like when someone refers to Leonardo DiCaprio’s “Elvis stage”). Other than that, nothing much has changed in this future world: People drive the same cars and go to Pizza Hut and 7-Eleven. It’s all familiar and yet completely disarming.

This is pure, uncut stuff, and the fans will hit it like junkies clamoring for Substance D.

A SCANNER DARKLY ( * * * )

Directed by Richard Linklater. • Starring Keanu Reeves, Woody Harrelson, Winona Ryder and Robert Downey Jr. • R, 100 min. • At the Lighthouse Cinemas.