Bonnie Montgomery is the world's greatest detective. Not that anyone -- other than Grampa Banks -- has heard of her. But they will have heard of Montgomery Bonbon, the gentleman detective with the bristly mustache, fashionable beret, and accent that's hard to place. Montgomery Bonbon is responsible for solving many high-stakes crimes, including unmasking the Emmental Bandit, restoring the Rusakova diamonds to their rightful owner, and busting an international owl-smuggling ring, resulting in the arrest of over twelve owls. But now Montgomery Bonbon is needed on a case much closer to home, at the Hornville Museum in Bonnie's hometown of Widdlington, where a mysterious death has occurred. Don't look too carefully, however -- from certain angles, Montgomery Bonbon looks suspiciously like a ten-year-old girl.