This June, 750,000 fans were left disappointed when the King of Pop died just eight days before kicking off his 50 day stint at London's 02 Arena. Tour sponsors AEG had invested millions into what they believed was a guaranteed multiple return. Jackson's tickets sold at a ridiculous rate of 600 a minute at times and there was no doubt that his triumphant return after a ten year hiatus would be both a commercial and artistic success.

What a lot of people didn't predict was that he would die just days before the tour was due to start. Not a natural death either, but one which seemed to be a result of prescription pill addiction and an illegally administered dose of the anaesthetic Propofol.

The film "This Is It" is a film for people to see for themselves exactly what state of health and mind MJ was in days leading towards his death, as it details his rehearsals for the tour. Was he frail? Could he perform his complex and demanding dance routines? Was he up to 50 exhaustive dates? The answers to these questions are as complex as the man himself. He appears frail and underweight. At times he does not exert himself fully, but gives a fully reasonable explanation that he wants to "conserve his energy" for the big tour. Yet at times he utterly wows you with his sheer brilliance. His singing on numbers such as "The Way You Make Me Feel" and "Beat It" are note and pitch perfect. And I just love his energetic and inspired Dying Fly act at the end of "Beat It."

The documentary opens with the dancers on the tour who appear to be just beside themselves with excitement on auditioning for the King of Pop. You just can't help feel sorry that eventually their dreams must have been well and truly shattered. There follows a brief glimpse of an X Factor style of elimation, with Michael picking out dancers. "She's the one" he declares. What this film tells us that Michael seemed artistically in control. He knew what he wanted, he knew what worked and was an perfectionist to the last. He can often see and hear things that others can't. He is not a shambling wreck like some artists that have had drug problems such as Britney Spears or Whitney Houston. Eccentric, yes but that's just Michael Jackson. But with 45 years in the game he is just so professional and proficient at what he does. The dancers who are successful in passing the auditions as well as the musicians, appear to adore and are awestruck by Michael. He in turn inspires them and graciously tells his guitarist, the incredibly cool and badass Orianthi Panagoris that "It is her time to shine" during the guitar solos on "Beat It" and "They Don't Really Care About Us".

"This Is It" marks Michael as a brilliant artist but it is a documentary, so it is heavily edited. There is only so much the audience sees out of 100 hours of rehearsal footage, but that saying, that is the only bias. There is no voice over, no insiduous journalist (mentioning no names, Martin Bashir) focussing on all the negatives that detracted from Jackson's undoubted brilliance as a performer, such as speculation over his plastic surgery or alleged acts of child abuse. What you see are a number of people working very hard together to achieve something very special- Michael's comeback. "This Is It" wasn't going to be an ordinary show, because it's a Michael Jackson production and it is such a treat for Jackson fans to see what was sadly denied them. The best parts are continuation of the Smooth Criminal and Thriller themes, with new videos unveiled which were to be shown alongside the live shows. Giant mechanical spiders, 1000 strong marching soldiers (thanks to the effects of CGI) and scary ghouls hovering over the audience, this show was going to be very special indeed.

But what about Michael? In this documentary he appears focussed, dedicated and shows his extraordinary dancing and singing talents, which for a 50 year old man was nothing short of breathtaking. But there is something else that you just can't put your finger on- a distance, a detachment and the undeniable fact that the great man was terribly underweight. At times you could pick up on his fatigue, and I think that sums up this film. Undeniably brilliant, Michael still had it but piecing together the fact that he had already delayed the start of the concert, I believe that maybe he just wasn't ready for a full-blown 50 day tour. The film does not give us dates of his rehearsals. The audience are told the film was shot between March and June 2009, but we only see Michael in a handful of different outfits (including a coathanger shouldered Posh- Spice- a- like jacket with spangly jewels glittered down just one lapel) which suggests his rehearing wasn't that continuous but quite sporadic.

What this film does do, is give a lasting tribute to the great man because it is all about the music and the performing. Not just the final performance but the incredible hard work that goes into creating such a spectacular production. It is spellbinding and poignant to watch. I cried about three times, as at times Michael's beautiful singing voice really did touch my heart. At the end, the way he humbly thanked his dancers in the very same building, the Staples Center, LA, where his funeral service was to be held only weeks later was extremely moving.

It is a wonderful film, just under two hours long but for me, I was so absorbed, it just seemed to fly by. I tell myself that this is the way Michael would have wanted to go out- on a high with renewed respect for the performer and disregard to the other media fixations which dogged so much of his later life. And importantly, he came across as a genuinely lovely guy. A must see on many levels..