Mark Lawson talks to the controversial artists and 'living sculptures' Gilbert and George about their lives and careers. Since meeting as students at St Martins School of Art in 1967, Gilbert Proesch and George Passmore have forged an extraordinary artistic partnership ranging from photo-pieces and dirty word pictures to their latest postcard exhibition. Their vivid, graphic work set out to challenge the elitist art world through universal themes of identity, sex, class and nationality.