'Talib Kweli and Mos Def are Black Star' – thus proclaimed the cover of the duo's eponymous debut, released sixteen years ago. The prophecy has been fulfilled, and today the two are indeed stars in their own right, lighting up the night sky of cerebral, politically engaged hip-hop. After the release of their explosive, richly melodic debut, the two went their separate ways: Mos Def branched out into acting (remember 'The Hitchhiker's Guide to the Galaxy'?) and political stuntery (as in his arresting experiment with torture through force-feeding), while Kweli ploughed a less prominent, though no less distinguished, course through the world of indie hip-hop. A decade and a half on, the two reunite for a one-off gig at Le Trianon that promises to offer the final word in underground rap.