Dorothy Must Die is set in the world of Oz created by L. Frank Baum in his book series (George M. Hill Company, 1900-1920). The story borrows both from the books and the 1939 Wizard of Oz movie that starred Judy Garland as Dorothy. Baum originally wrote the books as if the stories were real and relayed to him by the characters, and the world of Dorothy Must Die hints at travel between the Land of Oz and Earth, suggesting that Paige nods to this tradition of storytelling. The Wonderful Wizard of Oz, the first book in Baum’s series, tells of Dorothy’s journey to Oz, and Paige uses that story as historical background. Years before Amy travels to Oz, Dorothy arrived via cyclone, was hailed as a sorceress for killing a wicked witch, and journeyed to the Emerald City, where she and her companions made history by seeking aid from the Wizard. Dorothy Must Die also pulls from The Lost Princess of Oz, which tells of how Ozma disappeared. In the original tale, Dorothy and the Wizard searched for Ozma, but Paige twists this story, instead making Dorothy responsible for Ozma’s disappearance.