On the possibility of a movie from The Lonely Island, the question seemed not "if" but "when." The answer to that is now. Popstar: Never Stop Never Stopping is written and produced by Andy Samberg, Jorma Taccone, and Akiva Schaffer. While Samberg, the most famous of the comedy/music trio, gets the lead role, it is the other two who share directing duties. This music mockumentary arrives nine years after the troupe's Hot Rod underperformed and it has grander ambitions, hailing from producer Judd Apatow, as did the subgenre's finest work in recent memory, Walk Hard: The Dewey Cox Story.

Samberg plays Conner Friel, who emerged as the star of The Style Boyz, a Beastie Boys-esque hip hop trio comprised of him and childhood friends Owen (Taccone) and Lawrence (Schaffer). Gradually casting a shadow over his collaborators, producer Owen and lyricist Lawrence, Conner launches a solo career as Conner4Real. Instead of the usual rags-to-riches approach that musician biopics and documentaries take, this one gives us a riches-to-rags story as Conner4Real's much-anticipated album is given ice cold reviews and puts up much smaller sales numbers than expected.

Conner and his entourage, which includes Tim Meadows as his road manager and Sarah Silverman as his publicist, take actions to correct the album's disappointments, landing foul-mouthed rapper Hunter the Hungry (Chris Redd) as the opening act of his concert. But it's clear to us that the real problem is that Conner has promoted himself at the expense of his friends and more talented collaborators. Lawrence has left the business and is working as a farmer in Colorado who makes unidentifiable wood carvings on the side. Meanwhile, Owen, whose musical input grows increasingly marginalized to the point where he is a DJ with a high capacity iPod, is asked to wear an electronic robot head during performances.

Naturally, Apatow and the Lonely Island gang have no difficulty getting real musicians to comment upon this fake one. Usher, Nas, Pink, Adam Levine, 50 Cent, Mariah Carey, Questlove, Seal, Snoop Dogg, Carrie Underwood, Ringo Starr, Michael Bolton, and DJ Khaled all appear as themselves, while Justin Timberlake amuses in a small role as Conner's personal chef and "Weird Al" Yankovic briefly shows up made up as a fictional musician. The celebrity cameos mostly entertain and lend realism to the movie, but the film doesn't rely excessively on them. It has fun playing with the notion of a vain, shallow, egotistical modern pop artist. Like other Apatow productions, one suspects this one left tons on the cutting room floor, the best of which we'll see in the inevitable unrated cut, deleted scenes section, and line-o-ramas.

Popstar never approaches Walk Hard levels of entertainment (or musicology), but it consistently diverts with silliness. Of course, this being a Lonely Island movie, the crude but clever silliness includes a number of original songs. Some of them, most notably the one in which Conner shares a girl's bin Laden raid-inspired proposition, are designed to shock and offend. Mostly, they're meant to show us that Conner is an idiot who deserves the failure he's facing. The songs are generally not too memorable; don't expect them to add another Oscar nomination to the one the trio got for their infectious win-worthy Lego Movie anthem "Everything Is Awesome." This is definitely not an Oscar movie, nor even a Golden Globes one (despite being one of the few films for whom Comedy or Musical designation would raise no eyebrows).

But it is generally a fun movie, the kind you expect this time of year from Apatow and Universal. The biggest laughs are ones that don't really make sense out of context and need not be described. There is a wildly on point parody of the "TMZ" show with Will Arnett sending up Harvey Levin (and Chelsea Peretti, Mike Birbiglia, and Eric André as his underlings) in a bit that you are glad to find resurfacing shortly into the end credits scroll. Unlike Walk Hard, Popstar doesn't pull plot points from biopics, preferring to invent its own ideas involving a beloved pet turtle, a seemingly shallow fianceé (Imogen Poots), an absurd wardrobe malfunction, and a ludicrous public disguise.

Samberg may be better known now than he was back in 2007 when Hot Rod came out, but he has still yet to prove himself as a theatrical draw, his only hits being the animated Hotel Transylvania movies. The best-case scenario for this is probably Get Him to the Greek numbers of $61 million domestic and $91 million worldwide. I'd think it's a lot more likely this performs closer to Walk Hard ($18 M domestic) and Keanu ($20 M to date) than one of Apatow's breakout hit comedies, with the height of moviegoing season and the intensity of summer competition more or less cancelling each other out.