A girl, a rising star of not quite the first magnitude, is courted by a budding astronaut. She is slightly condescending to him; has an affair with him but may have other lovers, or lover, at the same time. One day he is sent on the first expedition to a distant star; goes there and makes a successful return. Their positions have now changed. He is the most famous man in the country while her starrise has come to a stop at a moderate level. She is only too glad to have him now, but soon she realizes that he is not the same as he was before his flight. She cannot make out what the change is. Time goes, and she becomes concerned, then frightened, then panicky. I have more than one interesting denouement for this plot.
Nabokov’s plot pitch to Hitchcock (Via This Isn't Happiness)