John Candy plays Harry Crumb, the bumbling son who never quite lived up to the reputation of his sleuthing father and grandfather in his family's long-standing detective agency. Instead of running the company, he's been relegated to being a lowly trainee as their Tulsa office. Ineptitude is just what the CEO of the company, Eliot Draisen (Jeffrey Jones), in Los Angeles wants from an investigator for reasons of his own. Draisen flies out Crumb to Los Angeles to crack the case involving the kidnapping and ransom of Jennifer Downing, the beautiful heiress daughter of P.D. Downing (Barry Corbin) and his philandering new wife Helen (Annie Potts). Crumb begins to use his penchant for disguises to get to the bottom of things.