Sitcom writer Sir Roy Clarke looks back on one of his best-loved creations, Open All Hours. Roy shares his memories of working with two comedy legends: Ronnie Barker, who starred as the penny-pinching grocer Albert Arkwright, and David Jason, who played his hapless nephew Granville. The show was just one more success in Clarke's extraordinary career, sitting alongside his other long-running classic sitcoms Last of the Summer Wine and Keeping Up Appearances.