Stevie, a young Glaswegian just out of Barlinnie prison, comes down to London and gets a job on a building site - a melting pot of itinerant labourers from all over the country. Here, he has to contend with Mick, the bossy ganger trying - but usually failing - to control his workers Shem, Mo and Larry from Liverpool who know all the ropes but who never let work interfere with the main chance; and the other lads who each have their own scams as they duck and dive the rules and regulations of the building trade. Stevie has other problems to contend with: the wages are low, the site teems with rats; he has nowhere to sleep and life in London isn't that easy. One day, on his way to work. Stevie finds a handbag in a strip. He takes it back to its owner - and meets Susan. Susan, desperate to make a name as a singer, drifts through life, never quite getting it under control As Stevie and Susan learn to live with the ups and downs of life in London, RIFF-RAFF builds a portrait - sometimes gritty, often funny - of life as it is lived in the margins.