Sinuous and mysterious as a plume of drifting smoke, a new sort of groove wafted two decades ago from Bristol, a bohemian university town in the west of England. Though its prime movers — Massive Attack , Tricky and Portishead — all loathe the term, the word "trip-hop" has become synonymous with the style created by Bristol bands like Massive Attack and Smith & Mighty. The sensuous groove fulfilled a timeless human need for a bass-heavy sound to touch the secret recesses of the imagination and lure our dreamworld onto the dance floor. Trip-hop was tailor-made for the moment — and it happens every night — when a bopper wants to get tender. Or when domestic listeners seek to wander within themselves.

Not all local grooves take flight, but trip-hop most certainly did. Over the next two decades it was re-imagined as chill-out, downtempo, illbient and lounge music. Its subtle tendrils have woven into music round the world: Washington, D.C.'s Thievery Corporation , with their exotic cosmopolitan edge; drifty Brazilian sounds like Ceu , whose dulcet lilt earned her maximum market penetration (a Starbucks CD); London's Ninja Tunes' artists like Bonobo and Berlin's techno-tinged Sonar Kollektiv. As music writer Simon Reynolds notes, "People like Flying Lotus and Gonjasufi on the West Coast are doing trippy hip-hop. Though it's not quite the same thing, they probably are the inheritors of the spirit of Massive Attack, Tricky, Earthling and DJ Vadim."