Directed by Paul Thomas Anderson. Starring Joaquin Phoenix and Josh Brolin. Rated 14A. 

Sure, moments have dragged in The Master, Magnolia, and virtually everything else by Paul Thomas Anderson. But they always felt like part of the thorny writer-director’s greater mission to illuminate the darker folds of American life. Here, his cultural zingers—hilarious when they work—are surrounded by vast amounts of whatever.

Fortunately, the Masterful Joaquin Phoenix returns to centre a conspiracy-laden tale set in Southern California at the ass end of the 1960s. This time, though, there’s no Philip Seymour Hoffman to play against. Instead, Phoenix’s perpetually pot-hazed Larry “Doc” Sportello—a two-bit private dick in a seedy beachside community—is butted up against Josh Brolin’s “Bigfoot” Bjornsen, a brush-cut LAPD detective who beats suspects and plants evidence, while moonlighting as a movie extra and used-car pitchman on TV. He makes Doc’s life a living hell, while somehow seeming needy about it.

In other words, Bigfoot’s a whole-cloth creation of Thomas Pynchon, the circuitous-minded author of The Crying of Lot 49 and other essentially inadaptable novels, with this the first such attempt. With period music again augmented by Jonny Greenwood’s spooky score, the story that attends this remarkably passive title—referring vaguely to nautical law—finds Doc contacted by a flighty ex (an unconvincing Katherine Waterston). Her current bf, a real-estate developer played fleetingly by Eric Roberts, has been kidnapped.

Doc’s randomly mounted search for the dude leads him to encounters with various, mostly forgettable characters, played by the likes of Benicio Del Toro and a thoroughly disposable Reese Witherspoon. Martin Short stands out as a dentist with a coke fetish and Rodney Bingenheimer hair, and Owen Wilson warms things up as a snitch caught up in the Nixonian politics that inform the era’s paranoid vibe. The women here are all victims or vamps, dampening the fun, and it says something that Anderson chose to have his tale narrated by Joanna Newsom, whose squeaky, breathless voice only adds to the impenetrability.

Famously, the actors in the 1946 version of The Big Sleep—which also influenced The Big Lebowski, which this episodic stoner tale vaguely resembles—had almost no grasp of the plot, even after director Howard Hawks asked author Raymond Chandler to explain his book, which had been adapted by a well-pickled William Faulkner. But Bogart and Bacall compensated by speeding everything up and having a visibly good time. Everything in Vice, however, was born in the writer’s den, and far too much of it seems to stay there, with Anderson and Pynchon elbowing your ribs with giggly in-jokes that work best if your nitrous oxide doesn’t wear off in less than 148 minutes.