In this thrilling third installment of Monster Allergy, Zick and Elena return from summer vacation to start a new school year and continue their incredible adventures in Oldmill Village, a hideaway for all kinds of ghosts and monsters. Now these friends will have to face bullies, homework, and tests on top of Oldmill's usual monster shenanigans—including a new group of monsters that has just moved in next door! Then, when Elena's best friend, Charlie Shuster, comes to town, Zick is left feeling jealous. Like Zick, Charlie can see monsters, but otherwise the two couldn't be more different. However, when a school field trip turns into a submarine adventure and Zick must escape from aquatic phantoms, Zick and Elena learn that Charlie isn't quite what he seems. In this village full of monsters, anything can happen!