History within spitting distance: Anarchy at the National Film Theatre. Next week the NME's punk season gets under way. Ryan Gilbey discovers what the camera saw in it all

Films like DOA or Punk in London or The Great Rock'n'Roll Swindle are pretty much the only documentation left on punk. There's still the music, of course - there can be nothing like letting a room fill up with 'God Save The Queen'. But the sight of the Sex Pistols, the way those whelps played at their audience, leaning into them, like the lions baiting the Christians, you can't find this anywhere else. Film has preserved the era as history, something which, in its immediacy and velocity, it seemed inconceivable that punk would ever become.

Next week, the National Film Theatre and the New Musical Express launch 'Punk: Before and Beyond', a season that demonstrates pop's propensity to substantiate (and, in U2's Rattle and Hum and Depeche Mode's 101, aggrandise) itself through film. Bands have mostly forsaken the motion picture for the promo now. Much of what you'll find at the NFT - Blur's Star-Shaped, REM's Tourfilm - first surfaced on video, yet, cramped in there, can't fulfill its potential. And so with punk, a medium so confrontational it seems almost inhumane to box it into a television screen.

In DOA, a film diary of the Pistols' fateful 1978 US tour, the director Lech Kowalski zig-zags between the Stateside vaudeville and a decrepit, Orwellian London. Like Wolfgang Buld, who directed the sycophantic Punk in London, his outsider status lends him an insatiable appetite for the scene's minutiae; witness the way his camera prowls the crummy concrete labyrinths of north London estates. He plays a blinder, too, by giving the authorities free rein. Mary Whitehouse squats upon the First Amendment, questioning whether punks have the right to free speech, while an official whinges, 'I'm not going to listen to what they say until they learn to enunciate clearly and speak properly in the Queen's English.'

The film's major stylistic device, its collage effect, reveals a strand of sympathetic political reasoning in punk that, to many kindred spirits in 1978, may have been obscured by the movement's bile. Kowalski plots his graph meticulously, flitting between disenfranchised London school-leavers, their spokesmen the Pistols turkeying in San Francisco, and back to the governmental misanthropist bleating, 'They can't beat us, they're not going to beat us, I represent the status quo.' For Woodstock, film delivered nostalgia. For punk, it provides a lucidity which would have been impossible to arrive at outside the editing suite.

Even without hindsight, the glimpses of Sid and Nancy would feel horribly septic. He's in swastika T-shirt and wraparound shades; she's sporting a bleached fuzz, her deep, dead eyes like bullet-holes. It's odd how the legend has superseded the reality: you just coo at their resemblance to Gary Oldman and Chloe Webb. 'Shall we kiss for you?', Nancy offers, then notices her compadre. 'Please try and wake up, Sid' - he's nodded off, mid-sentence, his lit fag resting on the bedclothes - 'I'll make a cawfee.' Sid stirs and asks the camera, 'Do you wanna make a pornographic movie?' Pause. 'Give us a hundred quid.' Even when Nancy flashes her breasts, she still can't upstage Sid's comatose charisma.

The morbid thrill gives off quite a stench, and it's there too in Sonic Youth 1991: The Year Punk Broke, when Kurt Cobain goofs around in the sun, looking preppy in white socks and pumps. You keep waiting for a burst of vitriol or insanity, but he's deliriously happy playing Kevin Costner to Kim Gordon's Madonna backstage at Reading. Only later, belting out 'Smells Like Teen Spirit' and 'Negative Creep', does his death sink in, as he sails at the drum-kit, pounds his head against an amp, flails on bassist Chris Novoselic's back like Smike in Nicholas Nickleby.

Penelope Spheeris was first to commit to film America's laconic response to punk. Her 1981 film The Decline of Western Civilisation Part 1 falls between DOA's dystopia and Sonic Youth 1991's summer- camp tomfoolery. The often awesome Black Flag deliver an uncomfortable 'White Minority', but the dread is tempered by Darby Crash, dumpy frontman for the Germs. When the Germs began, Darby would paint himself with peanut butter and dive through broken glass to disguise the fact that his band couldn't play, displaying a selflessness unheard of in the music business.

Between 1978, when DOA and Shell Shock Rock, a portrait of the Belfast scene, were filmed, and 1981, when Decline emerged, punk had already changed shape. As the critic Greil Marcus notes, the LA scene didn't assault the establishment as the British punk scene had, 'because those who make LA punk are so often tracked to become those in power, to enjoy money and mobility without purpose'.

Whichever side of the Atlantic you're talking about, Mary Whitehouse was mistaken when she claimed that punk robbed youth of spirit. The sound of 'Bodies' crackling like spitting meat, the swagger of Sid Vicious attempting graceless scissor-jumps in DOA - pop music doesn't come any more spirited than this. During the 'Anarchy in the U K' guitar break, Johnny Rotten is quite still, fluffing his hair. It's a performance of obscene arrogance, and nobody, bar Prince or Public Enemy or the Jesus and Mary Chain, has even attempted to command a stage the way Rotten does.

But there's always Iggy. In the compilation Punk, he's carried to the mike a la James Brown, torso smeared with blood, for a simmering, sprawling plough through 'The Passenger'. With jet black crop, twitching hind, leather pants and prop chair, he's punk's own Sally Bowles. His kinetic ballet is exhilarating.

Punk also features sparky turns by the Buzzcocks, punk's misfits in white denim and coy smiles. 'Tricky guitar solo', announces Pete Shelley, prefacing the break in 'What Do I Get?' with brattish nonchalance before fouling it up. There was room in punk to be cocky, even when it flared up in your face. It glorified the ridiculous, the failed - a cherubic Billy Idol tarting about in front of Generation X is the former, the abominable Terry and the Idiots the latter. But the comedy of DOA can't negate the horror that the camera won't shy away from, and which only film can examine.

It comes in random flashes. Kowalski assembles a grainy montage of London schoolkids over which he lays Johnny Rotten, live, barking the grim mantra 'No future for you'. It's a trite juxtaposition until you realise that many of those children, now 16 years older, will be living out Rotten's words, they'll be proving him right, this copper-topped crazy who, body bent like Quasimodo, warned them that they would be swallowed by a void - he was right after all.

'Punk: Before and Beyond' runs from 1-31 August at the NFT (071-928 3232)

(Photograph omitted)