Mavis is thrilled to be reunited with her friends Sophie and Charlotte, twin werewolves from her Ghoul Scout troop. But when Aunt Lydia smells humans on the premises, she orders a lockdown of the castle and a search of the entire hotel. Mavis loves the idea of having her friends stay even longer than planned, but the twins are not. They're hiding a big secret that may put them straight in the path of Aunt Lydia's search party!