The beats go on: the rise of reggae's sinister side

As a musical of 'The Harder They Come' opens in the West End, Nick Hasted laments the loss of reggae's early idealism and the rise of a darker, more sinister tone

The opening of The Harder They Come at the Playhouse Theatre returns us with a bang to the moment reggae entered the world. There had been one-off ska hits from Jamaica before. But the 1972 Perry Henzell film this musical is based on, and the soundtrack album, mostly by its star, Jimmy Cliff, showed outsiders the Kingston streets, simmering with heat and violence, where the music was made. Playing "rude bwoy" Ivan Martin, a sweet-voiced country boy who comes to the city to make his fortune, is burnt by Jamaica's corrupt music industry, and in his fury becomes a gun-toting ghetto legend, Cliff offered a microcosm of reggae's impoverished roots, aspirations and eventual, bloody decline. Island Records' Jamaican boss, Chris Blackwell, modelled Bob Marley's early persona on this archetype, setting the stage for the 20th century's most globally potent superstar, and reggae's growth as an international force.

Kerry Mitchell and Dawn Reid's thrilling production, when it premiered at Theatre Royal Stratford East last year, brought exuberant West Indian crowds into the theatre. As they soaked up deathless Cliff tunes including the title song, "Many Rivers to Cross" and "You Can Get It if You Really Want", it became a celebration of what reggae can be at its best. But the story of what has really happened to the music since is more divisive. A generational and cultural chasm has opened up more total than anything in rock music, as the socially conscious sentiments Cliff (who wrote Bob Dylan's candidate for the greatest protest song, "Vietnam") specialises in have fallen away. The digital rhythms and sexually and violently explicit "slack" lyrics of the dancehall genre have largely taken its place. There are two kinds of reggae, representing two views of the world.

When I interviewed Cliff once, he was clear on how reggae's rhythms always intimately reflect its times. "We felt downtrodden, and the music expressed that," he said. "In the ska era, we were expressing the fact of independence, so the music was fast and upbeat. Music slowed down after that [in the mid-1960s, when Jamaica's corrupt economy crashed], people were looking for something to hold on to, it was slower still. And Rasta really took over, because it was the essence of roots."

Marley, of course, remains Rastafarianism's public face. He was carefully "whitened" musically when he reached Western ears with Blackwell's policy of judiciously applied rock guitars, and dismissed as a sonic force by hip West Indians almost immediately. But enough remained in albums such as Exodus of Rastafarianism's ghetto creed, often alien and apocalyptic to outsiders, for him to remain the music's lost prophet and totem. From Kingston to the Jamaican diaspora in Brixton, Handsworth and elsewhere, the 1970s and 1980s anyway provided ample opportunity to dig deeper into reggae's riches. Studios such as Lee "Scratch" Perry's Black Ark drew up blueprints for rumbling, bass-heavy dub music which continues to influence every sort of 21st-century music, Marley's errant Wailers bandmate Peter Tosh became The Rolling Stones' brooding accomplice, while other rock royalty including Dylan used Sly Dunbar and Robbie Shakespeare to give their music a Jamaican edge they barely understood. Jamaican DJ Kool Herc's "toasting", meanwhile, casually gave birth to rap, in the streets of late-1970s New York.

Today, reggae still has pop currency, as Sean Paul's recent ascendancy, or the still more youthful pop of Jamaican-American Sean Kingston, proves. But in its Jamaican heartland, as with soul and hip hop in the US, the dancehall scene has moved away from the politically rebellious, warmly organic music of the Sixties, Seventies and early Eighties. Instead, in the form of dancehall, the music continues to reflect its home country, in ways many find impossible to stomach. Favouring crude digital "versions" of existing rhythms and equally raw explicit, degrading lyrics over the anthemic songwriting of a Marley or Cliff, it was a ghetto reaction against the conscious "sufferation" songs which had proved so popular worldwide – an instinctive two fingers to the sainted Marley. The prevalence of gunplay and lack of social concern in the lyrics came, more deeply, from a culture newly in thrall to crack. Jamaica subsequently exported drug gangsters as assiduously as it had once would-be prophets and sonic visionaries, even as the influence of US gangsta rap took its own cultural toll. The new music, which has left old reggae fans so bewildered, could hardly fail to be steeped in these new, unpleasant realities.

But there are still would-be prophets and showmen. Sizzla perhaps came closest to wearing Marley's crown. And though Buju Banton is best known to the general public for the early, homophobic-torture lyrics to his hit "Boom Bye Bye", his album 'Til Shiloh, marking his conversion to Rastafarianism and recorded with "real" instruments, marked a significant sea change in dancehall. Though his repentance from his earlier, sometimes vile attitudes has not been total, anyone who has seen his high-kicking, white-suited shows cannot fail to feel something higher and mightier – the sort of sensations which were once expected of reggae. Other stars such as Capleton have since converted to Rastafarianism. Like 'Til Shiloh's considerable international success, this perhaps shows a continued hankering for Marley, and the morally stern but loving world he portrayed.

Such nostalgia can be deceptive. Marley's Jamaica was one which saw his own attempted murder, the successful killing of Tosh, and Lee Perry eventually burning down his own studio in despair. If there was an organic warmth to the music they made which technology has deterred, this hardly sounds like a golden age. "Rude boy" lyrics and real gun-play are hardly new, as the narrative of The Harder They Come, in which Ivan becomes a folk hero while shooting corrupt policemen dead, doesn't shy from. Even ska veteran Desmond Dekker could be heard singing "slack" lyrics in the last year of his life.

And even if there is sometimes a feeling of doom and degradation in reggae, that doesn't account for Massive Attack's Meltdown extravaganza next month. These veterans of Bristol's 1980s reggae "blues" dances have collaborated with dub master Mad Professor in the past, and continue to champion the great sweet-voiced singer Horace Andy. In every minute of their continually cutting-edge careers, they are keeping the Black Ark, and its dub games with musical time and space, alive. As with the iconography and ideas of last year's best British film, Shane Meadows' This Is England, reggae refuses to die, or even lie still.

If you really want to consider the music's continuing potency, though, you could have done worse than watch Cliff himself, the last time he played London. The Harder They Come's deeply charismatic star rarely strays far from the soundtrack's songs, and those he wrote soon after, these days. But then, he doesn't need to. High-kicking and orating, new lyrics were added to the old tunes, improvised reactions to the newly apocalyptic world of "sufferation" we find ourselves in after 11 September, which didn't surprise him at all.

"Everybody comes into this planet in some kind of way – it has something to do with how we are," he told me when I spoke to him. "I was born in a hurricane." In the theatre next month, you'll feel that timeless, beautiful storm blowing again.

'The Harder They Come' runs at the Playhouse Theatre until 1 November (0870 060 6631)