NEW YORK (AP) — Spike Lee worked with Michael Jackson 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."