Eugene Winkleman is all set for a boring two-week vacation in Rochester, New York, when strange coincidences start to happen. First, he and his Uncle Mel see a movie about a monster called "Yobgorgle" that is supposed to live in Lake Ontario. Then Eugene actually meets the man who made the movie -- none other than the great Ambrose McFwain of the Piscean Discovery Institute. Professor McFwain is looking for an assistant to help him with his latest monster hunt. He hires Eugene! Between bites of Greaso-Whammy Burgers, Eugene has the craziest, strangest and funniest summer vacation that any boy has ever had.