Despite being a founding member of the biggest band in the history of rock music, George Harrison had a way of sneaking up on people. The media dubbed him The Quiet Beatle when the Fab Four first started to break out, he was overshadowed by John and Paul as the frontmen and then by Ringo when the movies were made(*) and tended to get a couple of songs per album in what seemed like an act of charity from the Lennon/McCartney songwriting duo. And yet he wrote one of the band's most enduring tracks in "Something" - so beautiful that even inveterate Beatle-hater Frank Sinatra called it one of the best love songs ever written - was the first Beatle to have a major solo success (with the "All Things Must Pass" triple album), helped inspire one of the great rock albums of all time ("Layla," which was based on Eric Clapton's attraction to Harrison's then-wife Pattie Boyd), kept the Monty Python film series alive and did a huge amount of charity work (most famously The Concert for Bangladesh). He lived a full, remarkable life, well beyond being the skinny guy who stood in between Jon and Paul on "The Ed Sullivan Show."

(*) Though George's big scene in "A Hard Day's Night" - where he shreds the middle-aged producer who's convinced he has his finger on the pulse of the youth market and yet can't recognize a Beatle in front of him - remains my favorite moment in the movie, and one of its most timeless.

Martin Scorsese's Harrison documentary, "George Harrison: Living in the Material World" (it airs tonight and tomorrow at 9 p.m. on HBO) snuck up on me in the same way. There are times when it seems too long and self-indulgent, and others when it seems like Scorsese couldn't decide whether to do a Harrison documentary or a Beatles documentary and tried to mash the two up - and yet its cumulative power is very impressive.

The film clocks in at nearly three and a half hours, with most of the first two (all of Part 1 and the beginning of Part 2) dealing with his time in The Beatles. There's arguably no way to tell the story of that part of Harrison's life without telling the story of the band, and the film gets candid interviews from Paul, Ringo, George Martin and nearly every other survivor of that period.

Astrid Kirchherr and Klaus Voormann, close friends of the band during their early days in Germany (and main characters in "Backbeat," the '94 fiction film about that period) explain how George served as a "catalyst" between the contrasting personalities of John and Paul. Ringo in turn notes that George had contrasting sides to his own personality: "The love, bag of beads personality, and the bag of anger. He was very black and white."

Along the way, Scorsese incorporates archival interviews with Harrison (who died of cancer in 2001) and ample footage of the group in those days - including Harrison's famous blow-up at McCartney during the recording of "Let It Be"(**) - and to the public and media reacting to Beatle-mania(***), and particularly of Harrison's introduction to the Indian music and spirituality that informed so much of the rest of his life.

(**) The "Let It Be" documentary itself has yet to be released on DVD, with media stories circulating that Paul and Ringo don't want younger generations to get a look at the band getting so nasty with each other.

(***) One of the documentary's funniest sequences features a white-haired British TV commentator trying to explain the phenomenon while Mick Jagger sits off to his right, struggling to keep a straight face.

But the film is definitely more compelling when it moves past the Fab Four. It glosses over the Harrison/Boyd/Clapton love triangle more than I would have liked, but almost makes up for that with some compelling Phil Spector interview footage (including the usual Spector hair weirdness) and with other segments - including Harrison stepping in to finance Monty Python's "The Life of Brian" when its religious content scared off more traditional film investors - illustrating the depth and breadth of his post-Beatles life.

Again and again in the film, either George himself or those close to him discuss his thoughts on mortality and life after death, and on his attempt to prepare for his soul to leave his body when the time came. All that discussion pays off beautifully in his widow Olivia's riveting account of the 1999 incident where Harrison - already battling throat cancer - was nearly killed in a knife attack by a mentally-ill intruder.

Unsurprisingly, all his friends and loved ones get choked up discussing Harrison's death - Ringo jokes through tears, "God, it's like Barbara fucking Walters in here, innit?" - and yet all seem in some way to have acquired some of Harrison's confidence about what awaited him after death. Tom Petty, who was in the supergroup The Traveling Wilburys with Harrison, Bob Dylan, Roy Orbison and Jeff Lynne, recalls Harrison calling him up the day Orbison died to reassure him, "He's still around. Just listen."

I went through an obsessive Beatles phase when I was younger. I read all the books, listened to all the albums, all the solo records, watched all the movies, etc. For me, there was little in "Living in the Material World" that was new. But the exhaustive nature of it, and the intimacy that Scorsese and his collaborators develop with both their subject and those who knew him, makes it into something more than a three-plus hour rehash of an oft-told tale. There are similar films to be made about other members of the band (and have been), but this one - especially the second half - illustrates why George's story is as worthy of telling as his more talkative, celebrated mates.

Alan Sepinwall may be reached at sepinwall@hitfix.com