He was known as "the quiet Beatle." He was certainly the most enigmatic. So Martin Scorsese's biographical documentary, George Harrison: Living in the Material World, is something of a revelation.

The two-part film, available on demand starting Thursday on HBO, is an intriguing portrait of the Beatles' junior partner and guitarist, who died of lung cancer in 2001.

It combines home movies, archival footage, and a landslide of priceless snapshots, professional photos, and recent interviews with Harrison's son Dhani, Paul McCartney, Ringo Starr, Billy Preston, George Martin, Eric Clapton, Phil Spector, and many others, conducted specifically for the film.

Of course there's a big absence here: the voice of John Lennon.

The soundtrack is loaded with Beatles' classics as well as Harrison's lovely, often underrated songs, such as "All Things Must Pass" and "My Sweet Lord."

Harrison was regarded by many as the most diffident of the Fab Four, a glorified sideman for Lennon and McCartney.

That's not the figure we get to know in Living in the Material World. Harrison was a confident, even cocky kid, with a pompadour that would make Donald Trump jealous. One of McCartney's friends described George's hair as "a turban."

He auditioned for the band by playing a song called "Raunchy" atop a double-decker bus as it rumbled through the streets of Liverpool.

While choppy at times, the film, over the course of its 31/2 hours, takes a substantive look at Harrison's life and career, from the moldy, subterranean clubs of Hamburg, Germany, to the international insanity that was Beatlemania, to the disillusioned discord of the Let It Be recording sessions.

There are some remarkable anecdotes along the way, such as George describing the circumstances of his first LSD trip with John. They were doped without their knowledge by their dentist, who slipped the drug into their after-dinner coffee.

Right. Who wants to go clubbing?

In his post-Beatle years, Harrison was primarily known for his fascination with Indian music and mysticism.

But the subject of Living in the Material World was anything but a detached swami. What emerges is a spirit just as complex and as conflicted as Lennon's.

As one intimate notes, "He was a man of extremes, whether it was meditation or cocaine."

Ringo says, "George had two incredible separate personalities. He had the love bag-of-beads personality. And the bag of anger."

Oddly, the more we get to know about the individual Beatles, the more we marvel at all they achieved together. As Harrison jokes in the film, "How many Beatles does it take to screw in a lightbulb? Four."