The two-hour documentary called "Bad 25", which has its world premiere at the Venice film festival on Friday, is a familiar mix of talking heads - choreographers, producers and stars - and film of concerts, rehearsals and music videos.

Released to coincide with the 25th anniversary of Jackson's acclaimed follow-up to "Thriller", Lee provides few surprises for Jackson aficionados, but paints a picture of a genius at work who cared about every step of the production process.

"I think that it was too many years we've ... concentrated on stuff about Michael Jackson that had nothing to do with the music," Lee told reporters, 25 years to the day after Bad hit the shelves.

The documentary, which Lee called his "love letter" to Jackson, has the backing both of the singer's estate and his record label, giving Lee access to many of the key players in the making of what is regarded as a milestone album.

"It was a chance to really dig into his creative process," he added.

"We all are blessed with the final work, but it's rare that you get to see how something is put together. We just see the final product. We don't see the blood, sweat and tears, all the work that goes into how the masters work."

Among the novelties is footage taken by Jackson himself, using a handheld camera, of Siedah Garrett singing "Man in the Mirror", the song she co-wrote for the star, a cappella save for an off-camera clicking of fingers laying down the beat.

There are also small yet enlightening insights and hints as to Jackson's true character, be it his interest in women, competitive spirit, professional drive or obsession over the smallest riff and dance step.

Garrett, for example, recalls how Jackson playfully threw popcorn at her as she tried to record "I Just Can't Stop Loving You", earning her, but not Jackson, a sharp rebuke from the onlooking producer Quincy Jones.

"NOT OF THIS WORLD"

Sheryl Crow said she was often asked whether Jackson became aroused when they performed a raunchy rendition of the song on his record-breaking "Bad" tour. She did not provide an answer.

Actress Tatiana Thumbtzen speculated that mint on the singer's breath suggested he may have been prepared for a kiss at the end of the "The Way You Make Me Feel" video, despite strict instructions only to embrace the singer.

Lawyer John Branca, who administers Jackson's estate following his death aged 50 in 2009, recalled a meeting Jackson arranged with his arch-rival Prince.

"It was not a happy meeting," he said, adding Prince had brought along a "voodoo box" which Jackson feared meant he was trying to cast a spell on him.

That rivalry was part of a competitive streak in Jackson that drove him to try to top the sensational success of his 1982 album "Thriller", still the best-selling album of all time, with Bad five years later.

He even scrawled "100,000,000" on his mirror to remind him of his target. While industry estimates vary widely, Thriller is estimated to have sold between 60-110 million copies worldwide, while Bad went on to sell 30-45 million.

Nothing, it seemed, was too trival. In one sequence, Jackson comically re-enacts exactly how he wants two animated characters who feature in a commercial to behave.

On a more serious level, Lee explores how Jackson's Afro-American roots were important to him, despite his gradually transforming facial features that made him appear more Caucasian.

Several interviewees could not contain their tears as they remembered when they heard of Jackson's passing, and several voiced their conviction at the time that it was not true.

Crow was among those who struggled to explain Jackson's talent. "The molecules changed in the room," she said of his presence. "He changed the molecules."

Near the end of Bad 25 there is a memorable live performance of "Man in the Mirror", after which Jackson holds his hands aloft to form the shape of a cross.

"Michael's not here to answer that. I cannot say he's trying to be Jesus Christ," Lee said in answer to a reporter's question.

"I'm not going to say that Michael was saying he was Jesus Christ, but you look at that performance - he's somewhere else. That's one of the greatest performances ever. You see the way Michael's singing that song, he is not of this world."

(Editing by Steve Addison)

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