It probably looks too easy on paper: a mockumentary making fun of the delusional nature of modern celebrities? Where the main character is heavily modeled on Justin Bieber, no less? Doesn't that just seem too simple, too obvious? Leave it to comedy troupe the Lonely Island (Andy Samberg, Akiva Schaffer, and Jorma Taccone) to both take this premise seriously and use it as a jumping-off point for the kind of so-stupid-it's-genius hilarity that defined their SNL video shorts. Using the mockumentary format to edit down a conventional showbiz-comeback tale into an 86-minute barrage of rapid-fire jokes, Popstar: Never Stop Never Stopping is the funniest Hollywood comedy since 21 Jump Street, and the most stylistically daring would-be blockbuster since the Wachowskis set fire to mountains of Warner Bros' cash in order to make Speed Racer (no really, that movie is a fascinating cult gem (no, really!)). Not bad for a movie that's at least 30 percent dick jokes. The pop star of the title is one Conner4Real (Samberg), who was once a member of a white-boy rapper trio called the Style Boyz with Owen (Taccone) and Lawrence (Schaffer). While Owen and Lawrence were the actual talent in the group -- providing, respectively, the beats and the lyrics -- it's Conner who was launched to superstardom and a solo career after a hugely successful guest verse on a diva's hit single (Emma Stone, just one of many blink-and-you'll-miss-them cameos). The mockumentary catches up with Conner on the eve of the release of his second album, "Connquest," which turns out to be a career-annihilating catastrophe that leads to such PR disasters as a worldwide blackout and musician Seal getting mauled by wolves. Eventually, Conner is forced to reflect on the hollow nature of his fame as he considers a reunion with the Style Boyz. In fairness, this is hardly the freshest of movie plots: Dreamer finds fame, loses touch with his roots, then reconnects with his real friends and learns humility. And the last third of the film, in which Conner finds redemption with the Style Boyz, isn't as funny as what came before (keep in mind: It's still pretty damn funny). But the genius of Popstar is that the familiarity of its story allows Samberg, Taccone, and Schaffer (the three co-wrote the script, and Taccone and Schaffer co-directed) to string together a bunch of surreal, wildly different gags, never sticking with any idea for too long. The result is a movie that has the frenetic pacing and anything-could-happen shifts of a viral video, expanded to feature length. There are talking-head interviews with real-life musicians like ?uestlove, Ringo Starr, Nas, and Mariah Carey, as they discuss Conner4Real's career. There are outlandish music videos for songs like "Equal Rights,"" in which Conner declares his support for gay marriage while forcefully insisting to the audience that he himself is not gay. There are visualizations of social media, as Conner promotes his album and his fans attack him for his behavior, and appearances on Jimmy Fallon, and "old" clips from the early days of the Style Boyz. None of these are revolutionary ideas on their own, but the speed with which the Lonely Island run through them feels, at times, like it's capturing something essential about modern celebrity and maybe even modern life: Someone like Conner, dependent on the public's adoration via the Internet for his career, is caught in a hellish feedback loop as he tries to rehab his image through heavily staged gestures of "authenticity" that only make him look like more of a tool. Of course, that satire is undercut by an ending in which Conner is revealed to be a good friend and a good person after all -- maybe a tougher movie would have left him stuck in the hall of mirrors of his own narcissism forever. Then again, it's possible that this movie would have fallen apart (or would never have been produced in the first place) without a traditional character arc to anchor it, and if that's the case, the Lonely Island made the right choice. Popstar: Never Stop Never Stopping is a screamingly funny takedown of celebrity culture and its related excesses, as well as a movie that feels, in the best possible way, like a product of our overcaffeinated, constantly connected age.