As the story begins, and old woman and her thirty-year-old, mentally handicapped daughter, both named Lucynell Crater, are sitting on their porch. Tom Shiftlet, a wandering one-armed man, approaches them and comments on the beautiful sunset. The elder Lucynell Crater thinks he is a tramp. He notices their unused car and asks them whether they drive; the elder Lucynell Crater answers that the car hasn't run in fifteen years, since her husband died.
They continue to talk, and when she asks him who he is and where he comes from, he asks how she'll know he isn't lying when he does tell her. He reveals that he is a carpenter, and she offers to give him a place to stay and food to eat if he will do some work for her; he'll have to sleep in the old, unused car. The elder Lucynell Crater asks if he is single or married, and though he doesn't answer the question, he indicates that he is unmarried because he cannot find a woman innocent enough.
In his first week of work, Tom Shiftlet makes a lot of progress, and teaches the younger Lucynell, a deaf-mute, to say a few words. Her mother suggests that he teach her to say, "sugarpie," and it is obvious that she hopes they will get married. He decides that he is going to make the old car run again, and the elder Lucynell agrees to give him the money he needs to fix it. The next day, he has it running, and drives it out of the garage.
That night, the elder Lucynell Crater makes explicit her offer of her daughter as a wife. At first, Tom Shiftlet says he cannot get married because he has no money. But she argues that her daughter doesn't know the difference, and says that she will pay to paint the car by Saturday so that they can drive to the courthouse and get married. She also offers to give him money for a modest honeymoon, and he is convinced.
That Saturday, the three of them drive to the courthouse and the younger Lucynell Crater and Tom Shiftlet are married legally. But Tom Shiftlet says he is unsatisfied with the wedding, since "that was just something a woman in an office did, nothing but paper work and blood tests." They drop the elder Lucynell Crater off at the house, and she is clearly pained to say goodbye to her daughter since they have never been separated before; however, she expects to see them again after two days.
After driving one hundred miles, Tom Shiftlet stops at The Hot Spot, a restaurant. Lucynell promptly falls asleep on the counter. He buys her a plate of food and tells the boy working at the counter to give it to her when she wakes up; he explains that she is a hitchhiker and that he can't wait since he has to make it to Tuscaloosa. As he drives away, he sees the occasional sign reading, "Drive carefully. The life you save may be your own."
Soon, he picks up a boy wearing overalls who is hitchhiking with a suitcase. Tom Shiftlet begins to talk to the boy, who is unresponsive at first. He talks about his mother, whom he praises as "the best old mother in the world," and muses that the worst day of his life was when he left her. This is clearly making the boy uncomfortable. As Tom Shiftlet begins to tear up from talking about his angelic mother, the hitchhiking boy tells him, "You go to the devil! My old woman is a flea bag and yours is a stinking pole cat!" and throws himself from the passenger door. A storm cloud descends and it starts to rain as Tom Shiftlet continues to drive toward Mobile.
In his interactions with the Lucynell Craters, Tom Shiftlet has a chance to achieve Grace. He has been wandering and has no friends, and has found in this household a chance to work hard, watch a beautiful sunset every night, and live a quiet life. This opportunity is hinted at when he first approaches the two women sitting on the porch and turns his back to them to face the sunset: "He swung both his whole and his short arm up slowly so that they indicated an expanse of sky and his figure formed a crooked cross." That crooked cross embodied in his figure represents his chance at salvation. As he drives toward Mobile, having missed his chance, he prays, "Oh Lord! Break forth and wash the slime from this earth!"
Tom Shiftlet, like many other characters in O'Connor's short stories, is disenchanted with the state of the world. After the elder Lucynell Crater tells him that her car no longer runs, he says, "Nothing is like it used to be, lady... The world is almost rotten." Later, when he is fixing the car, he comments that "the trouble with the world was that nobody cared, or stopped and took any trouble." By the end of the story, after he has abandoned the younger Lucynell Crater and caused the hitchhiking boy to jump out of his car, he "felt that the rottenness of the world was about to engulf him."
O'Connor's use of simile hints at larger meaning in the story. As her mother and Tom Shiftlet make small talk about the sunset, the younger Lucynell Crater watches him "with a cautious sly look as if he were a bird that had come up very close." The first word he teaches her to say is "bird," implying that he is revealing a part of himself to her; they have a special form of communication. When Tom Shiftlet starts the old car for the first time in fifteen years, he has "an expression of serious modesty on his face as if he had just raised the dead." This little miracle, tied to the miracle of Jesus raising the dead Lazarus in the New Testament, links the car to Tom Shiftlet himself. He was dead, and in the Lucynell Craters has a chance at new life. When the elder Lucynell offers him her daughter in marriage, she says, "Lemme tell you something: there ain't any place in the world for a poor disabled friendless drifting man," almost as a threat, and "the ugly words settled in Mr. Siftlet's head like a group of buzzards in the top of a tree." As he gets the idea to take the car and abandon her daughter, his "smile stretched like a weary snake waking up by a fire." The snake simile suggests the devil, as opposed to his chance at salvation. He will choose to listen to this devil as he abandons Lucynell at The Hot Spot.
As in many of Flannery O'Connor's stories, weather is an important indicator of characters' moods and important moments. As Tom Shiftlet drives off with the younger Lucynell Crater in the car, supposedly to go on a honeymoon, "The early afternoon was clear and open and surrounded by pale blue sky;" he still has a chance to redeem himself. But after he abandons her at The Hot Spot, he has lost his chance at salvation; this moment is enforced by the weather: "Deep in the sky a storm was preparing very slowly and without thunder as if it meant to drain every drop of air from the earth before it broke." After the hitchhiking boy has thrown himself out the passenger door, all is really lost for Tom Shiftlet, and "there was a guffawing peal of thunder from behind and fantastic raindrops, like tin-can tops, crashed over the rear of Mr. Shiftlet's car."
The intensity of the weather is increased by its personification throughout the story. When Tom Shiftlet approaches the house of the Lucynell Craters at the beginning of the story, he leans to the side "as if the breeze were pushing him," with his face turned toward the sun "which appeared to be balancing itself on the peak of a small mountain." As Tom Shiftlet drives along slowly after the boy in the overalls has leapt from his car, "A cloud, the exact color of the boy's hat and shaped like a turnip, had descended over the sun, and another, worse looking, crouched behind the car."