Rivalry is a tale which turns everything you thought you knew about Cinderella on its head. Instead of step-sisters, Cinderella has an identical twin named Marcella. Instead of an evil step-mother, Cinderella has her biological mother who adores her but tragically can't seem to connect at all with Marcella, who has never quite felt loved at home. So when they go to the ball, Marcella is looking for someone to love her while Cinderella merely hopes for a pleasant evening out. As it happens, the prince decides he would like to marry Cinderella, but when he comes to return the glass slipper after the ball, it is Marcella who answers the door. The prince mistakes her for Cinderella, and she plays along...