If you're the kind of person who logs onto movie mistakes.com ? to complain about inconsistencies like Ben Hur wearing a wristwatch or Harry Potter leaning on a supposedly broken arm ? then you'll be keen to hear about Angela Allen.
She's just won Channel Four's lifetime achievement award from Women in Film and Television for her work as a script superviser ? someone who's in charge of continuity.
She's worked with many movie greats like Marilyn Monroe and Katherine Hepburn.
Angela Allen joins Martha to talk about what her job involves.