Four best friends (Tibby, Lena, Carmen & Bridget) who buy a mysterious pair of pants that fits each of them, despite their differing sizes, and makes whoever wears them feel fabulous. When faced with the prospect of spending their first summer apart, the pals decide they'll swap the pants so that each girl in turn can enjoy the magic. Four best girlfriends hatch a plan to stay connected with one another as their lives start off in different directions: they pass around a pair of secondhand jeans that fits each of their bodies perfectly.