"Go" really earns its "R" rating and I like that. The film unapologetically presents amoral characters, recreational drug use, marginally-sympathetic dope dealers and young people having sex with strangers, along with nudity, violence, gunplay and a car chase that actually packs some oomph, all set against a low-rent backdrop of L.A. raves and tacky Las Vegas glitz. This "Pulp Fiction Lite" wallows in recklessness and, in these oh-so-responsible times, there's something perversely refreshing about that.

For his second feature, "Swingers" director Doug Liman, working from newcomer John August's screenplay, weaves together three stories that spring from a single encounter at a grocery store. After following one plotline for roughly 30 minutes, he returns to the initial setting to launch into the second tale, then repeats the technique for the third, which flows into a conclusion that more or less wraps up all three stories. The fragmented, non-linear technique is ambitious and not altogether successful, but offers more than enough satisfying moments to make up for its weak points.

A big part of the fun in "Go" comes from the film's many surprises, so I'll keep the plot description as bare-bones as possible. It begins at a Los Angeles grocery, where checkout clerk Ronna (Sarah Polley) spends the Christmas holiday season working overtime, trying to earn enough money to avoid eviction from her apartment. Reluctantly, she agrees to work a shift for Simon (Desmond Askew), so he can vacation in Las Vegas with friends. Then soap opera actors Zack and Adam (Jay Mohr and Scott Wolf) show up at the store to buy drugs from Simon.

Plotline A begins when the entrepreneurial Ronna decides to make some extra cash by handling the drug deal herself. With two pals in tow, she visits Simon's dealer, Todd (Timothy Olyphant), leaving her friend Claire (Katie Holmes) as collateral while she conducts the business. Things go very wrong, leading her to pursue a risky backup plan at a nearby rave. Plotline B follows Simon and his buddies to Las Vegas, where some remarkably bad decisions result in a wild, and quite entertaining, chase scene. Plotline C chronicles the travails of Zack and Adam when they become involved with an extremely intense police officer (William Fichtner) and his equally bizarre wife (Jane Krakowski).

Ronna's storyline works primarily because of a hilarious depiction of life from the perspective of a kid whacked out on Ecstasy, and the considerable talents of Sarah Polley and Timothy Olyphant, two actors with wonderfully expressive eyes. Polley, so good in "The Sweet Hereafter, " is compelling here, managing to look defeated and determined simultaneously, and Olyphant proves adroit at blending a menacing stance with an off-kilter sexiness. Interestingly, "Dawson Creek's" Katie Holmes, the closest thing this film has to a traditionally nice character, is also the blandest.

The center story, focusing on the misadventures of Simon and his buddies in Las Vegas, provides the juiciest action and biggest laughs. Breckin Meyer is a hoot as Tiny, a Caucasian kid trying his damnedest to be black ("If you were any whiter, you'd be clear," snaps one of his friends), but the lion's share of the time is given to Simon and Marcus (Taye Diggs), whose trip to the Crazy Horse strip club turns into a riotous flight from a vengeful father and son. Director Liman, who dealt with Las Vegas and male bonding in "Swingers," seems most comfortable handling this segment, effortlessly blending repartee and action scenes. Desmond Askew and Taye Diggs make a great comic team, with Simon's skittering impulsiveness and Marcus' Tantric efforts at serenity balancing out beautifully.

The third storyline, featuring Jay Mohr and Scott Wolf, suffers by comparison. The couple's situation demands that they be nervous, but I still found their stammering and furtive glances tiresome. Thankfully, William Fichtner and Jane Krakowski are a scream, exuding a deliciously ominous forced peppiness during a tense dinner scene with the boys. The husband and wife clearly have an agenda beyond sharing Christmas cheer, and the payoff is memorable.

Of the countless movies patterned after "Pulp Fiction" (it's hard to believe that only five years have passed since Quentin Tarantino turned contemporary cinema upside down with that film), "Go" is the best one yet, due to Liman's assured direction, coupled with a well-constructed script, a generally strong cast, great editing and effective use of music. Is the film a triumph of style over substance? Of course, but this genre is based on the pursuit of style over everything. Had the characters been more substantial, their nihilistic behavior would have been hard to take, and in "Go," nastiness and irresponsibility is half the fun.