The McNeil family has always been professional hoaxers -- tricking bystanders into believing they're seeing legendary creatures like Bigfoot and the Loch Ness Monster. Unlike the rest of his family, twelve-year-old Grayson hates hoaxing and wants nothing to do with the business -- even when the McNeils land a huge job and must pull off four sea monster hoaxes in a week. But when things go disastrously wrong and Dad and Gramps go missing, Grayson and his brother, Curtis, are the only people who can finish the job and save their family.