Melissa, Amanda, and Frank (Pee Wee) Anderson are all ready to bid their parents "adieu" as they leave for Paris, but at the last minute, the babysitter cancels. Reluctantly, Mr. Anderson calls his sister Sally to step in. The children have never met her, but wacky Aunt Sally is an immediate hit; she lets them use green beans as walrus tusks, makes great Halloween costumes, and knows no limits on sweets. Best of all, she tells them unimaginable and riotously funny family stories. There's the one about the Fat Little Mean Girl, and then there is Maud, who shot 80 cougars. In the midst of the hilarity, though, some of her stories are a bit eerie — especially the ones about the Trolls. Aunt Sally swears all the stories are true: the Anderson children realize they have to look at their family in a new way.