A mere four months after his death, the rehearsal footage of Michael Jackson's aborted O2 concerts has been cobbled together for a final tribute to the King Of Pop. Featuring all his biggest hits - Billie Jean, Thriller, Smooth Criminal - this is, the film solemnly tells us, Jackson as we've never seen him before.

You can say that again. No longer the planet-conquering superstar of old, this is a troubled, worn-out Jackson who's clearly under the influence of the prescription drugs that killed him.

He forgets his lines, stumbles through dance moves and looks as if he'd rather be anywhere but here. Stick thin and ghostly white, he resembles not a man but one of Tim Burton's macabre caricatures.

The film itself is no better. It's like watching the DVD extras of a concert movie that never was - complete with often blurry footage, uninteresting and frequently inaudible dialogue and song snippets which, post production, have been propped up using the original masters.

Shot in Los Angeles between March and June of this year, it begins with the audition process as hundreds of hopefuls grab their crotches with the aim of landing a backing-dancer spot.

It's then showtime as Jackson, in orange drainpipes and with a silver jacket hanging pendulously from his shoulders, leads the lucky ones through hits such as Wanna Be Startin' Somethin', Bad and Earth Song. Don't expect to be moonwalking in the aisles mind, with the songs stopping and starting as the singer complains about a malfunctioning earpiece or issues vague instructions to his backing band.

As an exercise in wringing every last penny from Jackson's legacy, the movie may be a success. But if you're looking for a tribute to the man who once took pop to its absolute zenith, this most certainly isn't it.