"The Five-Forty-Eight" opens one rainy evening in Manhattan. Blake exits his office building, ready to catch the express train home to the suburbs. But when he steps out of the elevator on the ground floor, he sees that a woman is waiting for him. He recognizes her, but as readers, we do not as yet know who this woman is. Outside on the rainy sidewalk, Blake is spooked to realize that the woman is following him. He tries to evade her by stopping first in a bakery and then in a men's bar. Amid growing fear, he thinks back to his relationship with the woman who is following him, and readers finally learn her story.
Six months prior, Blake hired her as a secretary for his office. She was timid but pleasant enough, and a good secretary. But there were warning signs. Her handwriting, for example, was crude and irregular. Blake was shocked by it, imagining that it must indicate some inner disturbance. She also mentioned to Blake that recently, she had been in the hospital for months, and it was difficult to find work after that. Blake observed her but did not recognize these as warning signs; instead, one night, they stayed late at the office and he went back to her apartment with her. They had sex and she began weeping, but Blake was content and did not pay her tears any attention. He did notice, however, a note in her apartment for the cleaning lady, scrawled in her horrible handwriting. The next day, during her lunch break, he instructed personnel to fire her when she returned. He took the rest of the afternoon off. She came to the office a few days later wanting to see him, but he did not let her in. He had not seen her since.
Back at the men's bar, Blake realizes he has missed the express and will have to catch the five-forty-eight local train. He walks quickly to the station; no one seems to be following him. He arrives at the station and settles into his seat on the train. The narrator describes him as a nondescript, slender man with brown hair and monochromatic clothing, but with unpleasant tastes lingering behind his eyes. He notices two neighbors sitting near him on the train: Mrs. Compton and Mr. Watkins. Mrs. Compton is a friend of Blake's wife, Louise, and hears about their marital troubles enough to dislike him. Recently, Blake had come home to find an absence of supper on the table and empty gin bottles. He told Louise he wouldn't speak to her for two weeks, and circled the date on the calendar. She protested, but he didn't care; she once was physically attractive, but no longer, and there was not much else she had going for her. It had been nine years since Blake installed a bookcase as a barrier between their rooms. He thought all of this was normal for husbands and wives. Mr. Watkins was a different story; Blake looked down on him for his long hair and his rented, instead of owned, house. Mr. Watkins and Blake had an argument recently when Blake objected to his oldest son, Charlie, befriending Mr. Watkins' son.
The train takes off from the station and Blake settles in comfortably for the ride. All of a sudden, someone says his name. It is the woman who had been following him. Blake remembers her name: Miss Dent. She sits down, crying slightly, and they begin haltering small talk. Blake knows something is wrong and tries to move to the next car, but she tells him that she has a pistol and will kill him if he moves. As the train continues, Miss Dent holds Blake hostage in his seat. She wanders in and out of lucidness, speaking about her sanity, her capacity for dreams, her time in the hospital, and how much she hates him. She forces him to read a letter, in which she addresses him as "husband." Blake tries and fails to remain calm, forcing himself to believe that someone on the train—maybe Mrs. Compton or Mr. Watkins—will notice his predicament and rescue him. However, this is to no avail: the train pulls into his stop, Shady Hill, and Miss Dent forces him out. They walk away from the station in the waning light. Miss Dent forces him to kneel in the dirt and then lie down fully. Blake weeps in the ground. Miss Dent continues monologuing until she has had enough and feels she has taken sufficient revenge. She leaves him in the dirt and walks back to the train station. Blake realizes that he is safe again, dusts himself off, and walks home.
