After having skirmished with a number of dangerous monsters on her home dimension of Mewni, Star Butterfly is sent to Earth by her parents. She arrives in the town of Echo Creek to live with the Diaz family. However, rather than living a normal life, Star, with Marco Diaz, continues to battle villains throughout the universe and in their high school, mainly to protect her extremely powerful wand, an object that she is still yet to master.