Rent Gangsta Granny (2013)

When Mum and Dad drop schoolboy Ben off to stay at his granny's for the evening, he expects the usual - boring old cabbage soup, never-ending knitting and endless scrabble with his equally boring grandma. Until one day, Ben's granny tells him an incredible story… that she was once known as the 'Black Cat', a notorious international jewel thief! Together they go on a wild adventure to complete the one heist she never quite managed in her criminal heyday - to break into the Tower of London, and steal the crown jewels.