focuses on a boarding house in a town that is not quite big enough to be a city: "The town was old enough to have slums, large enough to have no specific 'tracks' with a right and a wrong side." The town itself is an issue only for Philip Halvorsen, who while walking home becomes deeply disturbed by looking at guns in a pawnshop window and by the signs in the red-light district that urge him to take a sexual interest in matters that do not interest him, sexually or otherwise. These experiences suggest to him that he may be a deviant human being—someone who does not have the urges that average people do.

The boarding house itself "was big and warm and full of friends"; it is also a laboratory for two alien beings from a distant planet who have come to earth to conduct...