It was completely fitting that it could not be an ordinary premiere. In the dead of night, at 1am today, a specially invited UK audience became one of the first to watch a film showing footage of Michael Jackson's final months.
The film opens with a sequence which explains the footage had been destined for Jackson's personal library, and would provide "a glimpse into the passion".
There was much whooping and cheering as the film quickly moved into Jackson's rehearsals, opening with Wanna Be Starting Something. What was immediately striking was how thin and bony Jackson was. Equally striking was how agile the singer was, moving like a man half his age and sounding at the top of his game.
The film provides glimpses of some of the elaborate arrangements planned for the shows. For example, his performance of Smooth Criminal opens with a film of the singer in a gangster movie with Humphrey Bogart and Edward G Robinson.
At 4am, after the premiere, the general public was allowed in for the first screenings: a weird time, by any standards, to be going to the pictures.
The timing was all part of Sony's strategy of making the movie, This Is It, a cinematic event rather than a run-of-the-mill release. While it was the middle of the night for London, it was 6pm in Los Angeles, where the Jackson family were due to attend, and 10am in Seoul – three of the 15 cities hosting simultaneous premieres.
In London, red-carpet guests were in attendance, including X-Factor alumni JLS, as well as Harry Connick Jr and Westlife.
This Is It has been distilled into a film from 120 hours of rehearsal footage for Jackson's planned 50 comeback gigs at the O2 in London. According to the film's director, Kenny Ortega, Jackson is in control of himself and excited about the shows.
Ortega told the New York Times: "Was he slight? Yes. Was he frail? At times. But we had a strong and excited, happy and determined Michael. He wanted to do this more than anything he's ever wanted to do, and he was involved in every aspect of this project. That's the truth. It really is."
Filming began in March, when Jackson announced the gigs, and continued until his death, aged 50, on 25 June after a suspected heart attack. The LA coroner has blamed drugs he was taking including propofol, a general anaesthetic.
Jackson's friend Elizabeth Taylor used Twitter to praise the film in 18 tweets, including: "It is the single most brilliant piece of filmmaking I have ever seen."
The appetite to see the film has been immense. When a memorial to Jackson was held in July it was shown on TV stations across the world, attracting an estimated TV audience of a billion people. Sony bought the rehearsal footage of Jackson rehearsing in Los Angeles for $60m (£36m) and the film will open at 18,000 cinemas across the world, showing for two weeks only. The singer will be seen rehearsing more than 20 songs, from Thriller and Billie Jean to Wanna Be Startin' Something.
Perhaps inevitably, there have been accusations that the film puts a positive gloss on Jackson's final months. One protest website, this-is-not-it.com, claims the film covers up the singer's declining health. The accusation is vigorously denied by Sony and the filmmakers. Ortega, who choreographed Dirty Dancing in 1987 and directed all three High School Musical movies, told BBC Radio 4's Front Row: "This was a project that was close to his heart and had great meaning and reason. He didn't want to go out just because he could, he wanted to go out because there was reason."
The campaign's British spokesperson Mimi Flynn, from London, said she was one of a small group of fans who had got to know the singer well: "The pressure of the shows was too much for him. He was human, he had weaknesses. He had huge problems with insomnia exacerbated by the anxiety and pressure of the shows." Although not calling for a boycott of the film, Flynn said the "perfectionist" Jackson would "cringe" at the idea of rehearsal footage being shown.
