Watch Movies2Watch. It is based on the popular West End stage comedy by Terrence Rattigan. It all begins when Diana (Ellen Drew), the sister of a British boy studying in France, arrives in town to flirt with all of her brothers' schoolmates. Alan (Ray Milland), one of the students, successfully resists Diana's charms-meaning of course that Alan and Diana will be in each other's arms by fadeout time. (AllMovie)