KEVIN MAZUR / WireImage.com 1 / 5
KEVIN MAZUR / WireImage.com 1 / 5

"This is It," an unreleased Michael Jackson song, was released at the stroke of midnight on Oct. 12 on MichaelJackson.com.

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"This Is It," featuring backing vocals by Michael's brothers The Jacksons, plays during the closing sequence of Sony Pictures' upcoming film, 'Michael Jackson's This Is It,' and is included on the two-disc CD set Michael Jackson's This Is It, which is the stand-alone companion to the motion picture.

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Later this month, Sony Music Entertainment's Columbia/Epic Label Group will release the album internationally on October 26th and in North America on October 27th to coincide with the worldwide release of the motion picture, which arrives in theaters on October 28th and runs for a limited two-week engagement.

Disc one features the original album masters of some of Michael's biggest hits, including "Billie Jean," "Smooth Criminal," "Human Nature," and "Thriller" arranged in the same sequence as they appear in the film.

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Disc two offers fans a rare listen to the early demo versions of such classics as "She's Out Of My Life," "Wanna Be Startin'," "Somethin'," and "Beat It." This disc also features a recently discovered spoken word poem from Jackson entitled "Planet Earth."

Michael Jackson's This Is It also includes a 36-page, commemorative booklet featuring exclusive photos of Michael from his last rehearsal.