In October, HBO will debut Martin Scorsese's two-part documentary, George Harrison: Living in a Material World, nearly a decade since the "quiet" Beatle died of lung cancer. The documentary, which was first pitched to Scorsese by Harrison's widow Olivia in 2005, includes new interviews with Paul McCartney, Ringo Starr, Yoko Ono, George Martin, Tom Petty, and Eric Clapton (who recalls watching Harrison write "Here Comes the Sun"). Watch the trailer below:

Scorsese says that the heart of the film lies in Harrison's spiritual quest, which started once the Beatles first became successful: "He was trying to find a way to simplicity, a way to live truthfully and compassionately. It was never a straight line, but that's not the point. I think he found an understanding: that there's no such thing as 'success' - there's just the path," said Scorsese.

Rolling Stone says that two of the film's most powerful moments come from interviews with Harrison's fellow Beatles: McCartney makes an impassioned argument that anyone who thinks only he and Lennon were important in the group is wildly wrong; and Starr begins to weep when he recalls visiting Harrison as the guitarist battled terminal lung cancer. The two-part documentary will premiere on HBO on October 5 and 6.