Like Many of the Sex Pistol's gigs, Thursday night's screening of The Great Rock'n'Roll Swindle almost failed to happen. The finale of the British Film Tour organised by slacker manual Dazed and Confused was threatened when representatives of the surviving members of the band withdrew their permission to show the 35mm movie. Their reason? The film was to be introduced by their ex-manager, Malcolm McLaren, once described by John Lydon as "the most evil man alive". However, nostalgia junkies were rescued from a night in front of UK Gold when Dazed and Confused discovered that Polygram owned the sole rights to the video version, and secured this as a blearily magnified substitute.

McLaren, now as respectable as your dad, took to the mike and anecdoted away with his characteristic air of questionably raffish charm. It's difficult to connect this suited sweetie with the bollock-naked loudmouth who sloshes about on screen in a bath of snot-green liquid, but his tasteful tie is a decoy for the odd surge of unreconstructed cockiness. Seventeen years after the film he wrote and produced was taken out of his hands and mercilessly recut, the loss of certain scenes is still a passionate disappointment to McLaren: he particularly laments the absence of bizarre fantasy sequences lampooning Richard Branson and "a young man by the name of Sting".

The Swindle is still as good a con as it ever was, and it has a sleazy audacity as winning as anything in Orton. It boasts cameos from comedy empress Irene Handl and porno tragi-queen Mary Millington, and there are some good period gags (the script places Branson in a mansion that "overlooked the tomb of Karl Marx and the bedroom of Lynsey de Paul"). Stylistically, it's elusive: the meandering exoticism of its Ronnie-Biggs-in-Rio section and McLaren's brazen sermons to camera suggest an ancestor in Welles's F for Fake, yet it's also like a soft-porn hybrid of A Hard Day's Night and The Kenny Everett Show. Watching the film in a cinema built into a Bayswater shopping centre did nothing to make it a more heimlich experience: as the protagonists vomit, gob and bottle-chuck their way to filthy lucre, the audience quietly sipped the sponsor's gin - with tonic, ice and stirrer - and carefully put the empties under their seats. Dazed and Confused editor Jefferson Hack got closest to anarchy by lighting up in the no-smoking auditorium.

After the screening, I collared Malcolm McLaren in the foyer and discovered a man still enthused and amused by his cinematic debut, created, he reasons, "to make a statement that would keep the Sex Pistols as an idea intact. And also to prevent it from sitting in one of those well-anointed rock'n'roll almanacs. The jury shall forever remain out. I love that. That's really rock'n'roll." And with Lydon, Paul Cook, Steve Jones and Glen Matlock recently back together for a money-spinning tour, perhaps the time is right for a sequel? "Oh, I hope so. I'm working on that."