Monster High: Ghouls Rule unearths an old conflict between "Normies" and monsters - and things are about to get scary! For years, students at Monster High were warned that Halloween was a night to stay inside and avoid conflict at all costs. But Frankie and her friends discover that ghouls and "Normies" once loved to spend the holiday together! The ghouls decide to turn back the clock and use the night to celebrate their individuality and show that it's okay to "Be Yourself. Be Unique. Be a Monster!"
To free Baba Yaga and Renfield from the clutches of Monster Hunter Mila Starr, the Wishbone Family once more transforms into a Vampire, Frankenstein's Monster, a Mummy and a Werewolf but when aided by their three pet bats, the Monster Family zooms around the world again to save their friends, make new monstrous acquaintances.
After Monster High’s roller skating team is defeated at the Skulltimate Roller Maze tournament, the ghouls team up to face an all-boys league, with the hope of winning back the school crest and restoring school spirit.