Who's That Girl features a strait-laced character engaged with a woman he does not love, while a wild woman distracts him from his wedding preparations. Griffin Dunne plays Loudon Trott, an attorney engaged to the daughter of his boss. Madonna plays Nikki Finn, a recently paroled criminal. One of the many tasks of his day, Trott gets Nikki to the bus station, while she has ideas of her own - prove her innocence, which takes him all across New York City.