Julia McKenzie stars as David Walliams' cat-burgling GANGSTA GRANNY, in this one-off Christmas special based on Walliams' best-selling children's book. The story follows schoolboy Ben, who, after years of suffering his Gran's boring scrabble-games, cabbage soup and knitting, learns the shocking truth - Gran was one known as the notorious 'Black Cat', an international jewel thief! Julia McKenzie stars as David Walliams' cat-burgling GANGSTA GRANNY, in this one-off Christmas special based on Walliams' best-selling children's book. The story follows schoolboy Ben, who, after years of suffering his Gran's boring scrabble-games, cabbage soup and knitting, learns the shocking truth - Gran was one known as the notorious 'Black Cat', an international jewel thief! GANGSTA GRANNY boasts a superb cast of comedy greats including Miranda Hart, Rob Brydon, Joanna Lumley and Walliams himself.