Vladimir Propp analyzed 100 stories and found that they all contained 8 main character types that fulfilled specific functions to advance the plot, regardless of their individual differences. These 8 types are the hero, villain, princess, donor, helper, princess' father, false hero, and dispatcher. While Propp's theory focused on fairy tales, it is debatable how well the 8 character types apply to horror stories, which typically lack a clear hero and happy ending.