Ever since Eric “Doodles” King and his friends saved Coney Island from Crumple Monster and its minions, Eric’s life has been changing faster than he ever expected. His parents’ divorce has gone through, his mom has moved to a deluxe apartment in Manhattan, and now she’s making him start all over at a fancy new private school. Suddenly, Eric’s trapped between two worlds – his old Coney Island friends and the rich, cool kids at his new school who treat him like a celebrity. At least, Eric thinks, his days of epic monster battles are behind him. But what he doesn’t realize is that the magic mermaid ink that brought his drawings to life hasn’t been destroyed like he thought. Quite the opposite, King Neptune has found a way to take the last remaining drops to create a new class of creatures perfectly designed to put New York City right back where it belongs – underwater. Now it’s up to Eric to rally Monster Club again and find a way to bring back Brickman, Bellybeast, Skelegurl, DecaSpyder, and RoboKillz so they can stop Neptune before it’s too late.