Spike Lee worked with Michael Jackson [1] and considered him a friend, but the director says even he learned a lot combing through footage of the icon for a planned documentary about the singer's "Bad" album.

Lee calls it a "treasure chest of findings."

"We have footage in this documentary that no one's ever seen, stuff that Michael shot himself, behind-the-scenes stuff," he said in an interview Monday. "We had complete access to the vaults of Michael Jackson. ... He wrote 60 demos for the `Bad' record. Only 11 made it. So we got to hear a lot of that stuff, too, so it was just a great experience."

He added: "You don't have to be a Michael Jackson-head to enjoy this."

Lee's documentary, which does not yet have an official title, will be part of a flood of material to celebrate the 25th anniversary of the "Bad" album, Jackson's follow-up to "Thriller" that included hits like the title track, "Smooth Criminal," `'The Way You Make Me Feel" and more. The album is being rereleased Sept.18 with additional tracks, a DVD and other bonus material; Lee's film is due to come out later this year, but no date has been set.

Besides Jackson's artistry, Lee said the documentary will show a more personal side of the late legend.

"He had a great sense of humor, and he was funny - so you'll see a lot of that stuff," he said.

Lee interviewed people ranging from Kanye West [2] to Mariah Carey [3] to L.A. Reid to Sheryl Crow [4], who was Jackson's background singer on the "Bad" tour.

"We really divided it into two things: Artists today who were influenced by Michael, and then people who worked side by side - musicians, songwriters, technicians, engineers, people at the label, who were all committed to Michael, to the follow-up to the biggest record of all time, which still is `Thriller.'"

Besides the documentary, Lee also plans to hold his now annual birthday tribute to Jackson in Prospect Park in Brooklyn, New York, on Aug. 25; Jackson would have turned 54 this year.

"This year we're going to focus on the `Bad' album, we're going to focus on the 25th anniversary, but at the same time we're going to play his full catalog, including the Jackson 5 and the Jacksons," he said. "It's going to be even bigger and better this year."

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