Pearl Jam have been celebrating their 20th anniversary this year with live shows, album reissues and an upcoming documentary directed by Oscar winner Cameron Crowe. While going through countless hours of video archives, Crowe found what he calls the "holy grail" and wasn't even sure if it existed. The footage he was referring to is PJ frontman Eddie Vedder and the late Nirvana singer Kurt Cobain sharing a slow dance.

Crowe was a guest on Late Night with Jimmy Falloon to discuss his latest project, PJ20.

"Kurt and Eddie Vedder had a little bit of a back-and-forth thing going on in the press," said the Almost Famous director. "They also were friends on the side, and there was this mythical piece of footage that happened while Eric Clapton is playing "Tears In Heaven" at the (1992 MTV) VMAs."

"Kurt and Eddie have a moment below the stage where they slow dance. And it's a beautiful moment. We didn't even know if the footage could be found. We found it and it's in the movie."

Watch the whole clip below. Vedder revealed at a news conference during the Toronto International Film Festival that he was hit with a wave of emotion the first time he watched the footage of Cobain and himself.

“You see Kurt look over and go like this,” Vedder began gesturing with a finger over his lips. "It’s not him saying, ‘Don’t tell anybody or keep a lid on this private moment,’ it was actually because on the stage above us Eric Clapton was playing 'Tears in Heaven', which is a pretty quiet song, and we were jumping up and down clapping."

Vedder added: “The first time I saw that footage it was incredibly emotional, I think just because he’s smiling and you just think, ‘If he just could’ve pulled through.’”

Kurt Cobain committed suicide just two years after that moment.

PJ20 will air on PBS October 21 at 9pm EST. Pearl Jam are currently on tour in Canada and will head to South America throughout November.

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