Alex Norton discovers how showbusiness has handled the portrayal of the Scottish accent. For over 100 years audiences have struggled to understand our braw brogue: silent Harry Lauder films attempted an accent in the captions, and in Hollywood's golden era , everyone wanted to paint their tonsils tartan- but as examples from Katharine Hepburn, Orson Welles and Richard Chamberlain show, they couldnae. Then Disney made Brave and proved that it disnae have to be all bad!

• Documentary