Cameron Crowe is shown with Mike McCready in Long Beach. (Vinyl Films & Tremolo Productions)

Cameron Crowe loves Pearl Jam almost as much as he loves Cameron Crowe.

As his irritating new film, “Pearl Jam Twenty,” attempts to document — rockument? — the great Seattle band’s two-decade history, Crowe can’t decide whether he wants to play narrator, interviewer, insider, subject or superfan. The “Almost Famous” director pops in and out of this thing like a self-congratulatory Waldo, happily tagging along with his pals instead of doing the messy work of asking tough questions.

The story begins not with the band, but with Crowe moving to Seattle in the ’80s as a hungry young rock journo. Hypnotized by the ripples of primordial sludge that would spawn grunge, he befriends guitarist Stone Gossard and bassist Jeff Ament — and spends the next two hours glossing over Pearl Jam’s knotted internecine dramas, either out of flattery or laziness.

What a drag. Here we have the band that never trusted the media to get its story right — and now that story is being muddled for posterity.

It arrives in an autumn rush of flannel-swaddled nostalgia. In 1991, Pearl Jam’s debut disc, “Ten,” helped trigger the alt-rock gold rush, alongside Nirvana’s “Nevermind” and the Red Hot Chili Peppers’ “Blood Sugar Sex Magik.”

Yet somehow, only one archival Kurt Cobain interview manages to penetrate the bubble of “Pearl Jam Twenty.” The only people Crowe talks to are the current members of Pearl Jam, Chris Cornell of Seattle buddy-band Soundgarden, a roadie, a few fans and . . . himself. No parents, no wives, no friends, no rivals, no critics, not one of the band’s four former drummers.

Crowe unfolds his tale chronologically, but vault footage keeps popping up without a time stamp, forcing us to guess the year based on frontman Eddie Vedder’s haircut.

For viewers who missed Pearl Jam’s thrilling splashdown in the Clinton years, this will be a perplexing introduction. Stories of the band’s rapid ascent, its suspicion of fame and its heated public fight with Ticketmaster are all retold in detail here, but the musicians aren’t asked to do much serious 21st-century reflection on them.

The most frustrating flashes of what could have been arrive when Vedder explains the group’s early songwriting process. “A lot of my job is taking what they bring and turning it into something,” he says. “If I close my eyes, where am I? What does this music mean?”

That thought illuminates this band’s entire creative trajectory. The first two Pearl Jam albums still bristle with a restlessness that the band has never fully reclaimed. Here, we see Vedder taking the reins, which causes the band to grow uncertain of itself and one another. But as soon as the rift surfaces, Crowe sweeps it under the rug, inexplicably flashing back to Ament’s childhood in Montana.

Most of the film’s other non sequiturs star Crowe himself. The band’s boozy performance at a party celebrating “Singles” — the 1992 rom-com that Crowe directed and Pearl Jam appeared in — is presented as a head-checking turning point for the band. Dubious. The director is also happy to poke fun at the media hoopla surrounding the group but pats himself on the back for a Rolling Stone cover story he penned about them in ’93.

He’s a lousy journalist here, consistently allergic to touchy subjects. When Vedder mentions his birth father — a family friend who died before Vedder knew they were related, inspiring some of the band’s best-loved songs — Crowe doesn’t ask him another word about it. When guitarist Mike McCready confesses to problems with addiction and a blackout on “Saturday Night Live,” Crowe doesn’t inquire about the fallout. When the band makes a big stink at the Grammys in 1996, Crowe doesn’t ask why they were even there in the first place. When the band laments the nine deaths that occurred during a concert at Denmark’s Roskilde Festival in 2000, and Gossard says the tragedy forced the band to change its approach, Crowe doesn’t ask how.

And with Pearl Jam’s second decade squeezed into the final quarter of the film, Crowe fails to illustrate exactly how the band survived such a tumultuous rise while cultivating one of the most loyal fan bases in rock history.

Don’t lose your voice screaming at your flat-screen over this. If you want to reconnect with the Pearl Jam of yore, suss out a copy of “Ten (Legacy Edition),” the 2009 ­re-release of the band’s debut.

The second disc is a remixed version of the album that scrapes away all of the gooey chorus effects and boomy reverbs that were spackled onto their songs so they could compete in the high-gloss radio market. It’s a revelation. You can finally hear who this band really was.

Maybe in another 20 years, someone will make a documentary that does the same.

American Masters: Pearl Jam Twenty

(21 / 2 hours) airs Friday at 9 p.m.
on WETA and at 9:40 p.m. on MPT.