Maybe being a rock star isn't as exciting as it sounds, after all.

In the captivating, insightful documentary of a hippie icon, "David Crosby: Remember My Name," the rock star with the droopy mustache gushes without a filter about having a lot of sex, taking too many drugs and making harmony-filled rock 'n' roll.

He also confesses without reservation to being a complete jerk to his lovers and bandmates. He admits that none of the friends with whom he made Rock Hall of Fame music in the Byrds and Crosby, Stills & Nash (& Young) will speak to him. Not Roger McGuinn, Stephen Stills, Neil Young or Graham Nash, with whom he conversed nearly every day for 45 years.

Rarely have we seen such an unvarnished, unflattering and revealingly real portrait of a music star.

"Do you ever wonder why you're still alive?" Crosby is asked in the film.

"I don't know. I have no idea, man," offers the singer, 77, who details his two or three heart attacks, eight heart stents, a liver transplant, diabetes and other health issues.

He's remarkably and refreshingly candid. There's no high-powered manager or meddling publicist to intervene with spin control.

Props to Crosby for opening up. Credit co-producer Cameron Crowe, the former teenage rock journalist turned "Almost Famous" filmmaker, for getting Crosby to turn on the fountain of truth; Crowe is the one posing the questions on the other side of the camera.

An extraordinary amount of territory — both factual and existential — is covered in 95 minutes, with plenty of music and vintage visuals to season the story as well as returns to landmarks such as the Kent State University campus, where four students were killed by the National Guard during a 1970 antiwar protest, sparking Young's song "Ohio."

Like many other rock stars, Crosby had a doting mother and an indifferent father, an Oscar-winning cinematographer who never told his son he loved him. The film doesn't belabor those issues but rather addresses the pivotal moments in Crosby's professional life, including his off-putting political rants during Byrds concerts.

There was a prison stint in the 1980s for drugs and guns during which the singer kicked heroin and cocaine and the final CSN performance — a painfully off-key rendition of "Silent Night" at the White House Christmas tree-lighting in 2015 with President Barack Obama visibly wincing at the disharmony.

But most crucial — and devastating — was the 1969 traffic death of his girlfriend Christine Hinton. Nash posits that Crosby has never been the same since.

The saving grace through all of these ups and downers is Crosby's voice. It's still quite pretty. He's a natural harmonizer, making music with two newer groups that he leads.

The documentary features footage of current-day Crosby leaving for another tour as Jan, his wife of 32 years, wonders whether he'll return.

One scene from 2017 finds Crosby, all by himself, doing a soundcheck with his voice and acoustic guitar at Ames Center in Burnsville.

The Twin Cities figures in another scene. Crosby is reminiscing with famed rock photographer Henry Diltz about a classic shot of the star in his heyday, smoking a joint while holding a pistol, decorated like an American flag, to his head.

Diltz says the photo was taken in Minneapolis. Crosby counters, "I've never been to Minneapolis."

Ah, always the contrarian. But he's still selling T-shirts emblazoned with that priceless photo at his shows.

If you see the outstanding "Remember My Name," you won't forget Crosby — or that image.