Mona, the show's main protagonist, is a young girl with a vivid imagination. She believes her hometown is overrun with supernatural monsters and she plans to stop them all and save the town on a daily basis. Her alter ego, Mona the Vampire, has a "vampire sense" which tingles every time something odd happens. Although Mona's imagination can cause trouble at times, her imagination has proven to save the day more often than not. Sometimes at the end of an episode, they give hints that Mona was telling the truth all along.