For all of the middle ages, almost everybody believed that earlier in church history, there had been a pope who was, instead of being male,  a woman, who  met, alas, a Bad End. She wasn't there, as some people suspected then, and as we know now, but the story is so damn good it's hard to let go of. Whichever version of the story you're dealing with. Anne explains the different versions of Pope Joan and how we know she wasn't there, and Michelle is delighted by the vast amount of popular works telling her story. Musicals! No kidding! And too many novels to list.