Dr. Aqua is an antagonist that appears in the twenty-ninth Give Yourself Goosebumps book, Invaders from the Big Screen.
Dr. Aqua is a mad scientist and the main antagonist of the movie Agent Z vs. Dr. Aqua. His goal is to flood the world using his Flooding Machine and populate the waters with his minions, the humanigators, who are a mix of human and alligator.