The novel describes how, over the course of three days, Julian English destroys himself with a series of impulsive acts, culminating in suicide. O'Hara never gives any obvious cause or explanation for his behavior, which is apparently predestined by his character.
Facts about Julian gradually emerge throughout the novel. He is about thirty. He is college-educated, owns a well-established Cadillac dealership, and within the Gibbsville community belongs to the high-ranking "Lantenengo street crowd."
Our introduction to him comes seven pages into the novel, in the thoughts of the wife of one of his employees: "She wouldn't trade her life for Caroline English's, not if you paid her. She wondered if Julian and Caroline were having another one of their battle royals." Within the three-day time span of the novel, Julian gets drunk several times. One almost lyrical long paragraph describes one of his hangovers. During the first of two suicidal reveries, we learn that his greatest fear is that he will eventually lose his wife to another man. Yet within three days, he propositions two women, succeeding once, with an ease and confidence that suggest that this is well-practised behavior.
On successive days, he commits three impulsive acts of not-quite-unforgivable behavior in social situations, which are serious enough to damage his reputation, his business, and his relationship with his wife.
First, he throws a drink in the face of Harry Reilly, a man who, we learn later, is an important investor in his business. The man is a sufficiently well-connected Catholic that Julian knows word will spread among the Gibbsville Catholic community, many of whom are his customers.
In a curious device, repeated for each of the incidents, the omniscient narrator never actually shows us the details of the incident. He shows us Julian fantasizing in great detail about throwing the drink; but, we are told, "he knew he would not throw the drink" because he was in financial debt to Harry and because "people would say he was sore because Reilly ... was elaborately attentive to Caroline English." The narrator's vision shifts elsewhere, and several pages later we surprised to hear a character report "Jeezozz H. Kee-rist! Julian English just threw a highball in Harry Reilly's face!"
The second event occurs at a roadhouse, where Julian goes with his wife and some friends. Julian gets drunk and invites a provocatively-clad woman to go out to his car with him. The woman is, in fact, a gangster's girlfriend, and one of the gangster's men is present, sent to keep an eye on her. Both Julian's wife and the gangster's aide see the couple leave. What actually happens in the car is left ambiguous but is unimportant, since all observers assume that a sexual encounter has taken place. There is not apparently any concern that the incident has placed Julian's life in danger. However, the gangster is a valued automobile customer who in the past has recommended Julian's dealership to his acquaintances.
As Julian is driven home, pretending to be asleep, he "felt the tremendous excitement, the great thrilling lump in the chest and abdomen that comes before the administering of an unknown, well-deserved punishment. He knew he was in for it."
Third, the next day, he engages in a complicated brawl with a man, Froggy Ogden. Julian thought of Froggy as an old friend, but Froggy acknowledges to Julian that he has always detested him and did not want Julian's wife (Froggy's cousin) to marry him. In the brawl, which perhaps Froggy started, he slugs Froggy, and at least one of a group of bystanders in the club.
He experiences two suicidal reveries which are at odd contrast to each other. In the first, following Caroline's temporary departure, he holds a gun to his head:
- Julian thought and thought about Caroline and Harry, and thought against them, against their being drawn to each other sexually, which was the big thing that mattered. "By God, no one else will have her in bed," he said, to the empty office. And immediately began the worst fear he had ever known that this day, this week, this minute, next year, sometime she would open herself to another man and close herself around him. Oh, if she did that it would be forever.
He does not, however, follow through. His second suicidal reverie follows a failed attempt to seduce a woman, the local society reporter. He believes that as a result of his behavior, and the community's sympathy for Caroline, "no girl in Gibbsvilleworth havingwould risk the loss of reputation which would be her punishment for getting herself identified with him." He believes that even if he divorces Caroline he is destined to spend the rest of his life hearing:
- No, let's not have him, he's one of the older guys. Wish Julian English would act his age.... No thanks, Julian, I'd rather walk. No thinks, Mr. English, I haven't much farther to go. Julian, I wish you wouldn't call me so much. My father gets furious. You better leave me at the corner becuss if my old man. Listen, you, leave my sister alone.
Apparently finding this, and other indications that he had misperceived his status, too much to face, he commits suicide by carbon monoxide poisoning, running his car in a closed garage.
Although Julian faced many difficulties, some external and many self-inflicted, it seems clear that these difficulties, though serious, were not insurmountable. His wife has departed temporarily for a long talk with her mother, but she and the reader realize that she will forgive Julian. His business was in financial difficulties, but they do not seem insoluble. It even seems likely that he could have patched things up with Harry O'Reilly, who says, on learning of English's suicide, "I liked English and he liked me, otherwise he wouldn't have borrowed money from me... He was a real gentleman. I wonder what in God's name would make him do a thing like that?" and picks up the telephone to order flowers."
Biographer Frank MacShane writes "The excessiveness of Julian's suicide is what makes Appointment in Samarra so much a part of its time. Julian doesn't belong to Fitzgerald's Jazz Age; he is ten years younger and belongs to what came to be called the hangover generation, the young people who grew up accustomed to the good life without having to earn it. This is the generation that had so little to defend itself with when the depression came in 1929."
The title is a reference to W. Somerset Maugham's retelling of an old story, which appears opposite the title page of the novel. A merchant's servant tells him that in the Bagdad marketplace a woman, whom the servant recognizes to be Death, has just made a threatening gesture toward him. Borrowing the merchant's horse, he flees at top speed to Samarra, a distance of about 75 miles (125 km) and an almost impossible day's journey. The merchant asks Death why she made the threatening gesture. She replies "It was only a start of surprise. I was astonished to see him in Bagdad, for I had an appointment with him tonight in Samarra." In his introduction to the 1952 reprint, O'Hara says that he got the idea for the title when Dorothy Parker showed him the story in Maugham's play, Sheppy. He says "Dorothy didn't like the title, [publisher] Alfred Harcourt didn't like the title, his editors didn't like it, nobody liked it but me." O'Hara describes it as a reference to "the inevitability of Julian English's death."
In the 1930s it was unusual to mention brand names in fiction. Biographer Frank MacShane says that O'Hara wanted his book to have a similar authenticity to those of F. Scott Fitzgerald, whom O'Hara admired as a writer who "could come right out and say 'Locomobile' instead of 'high-powered motor car.'" MacShane says O'Hara "filled [Appointment in Samarra] with the names of popular songs, politicians, sports figures and cars of the period." English is a car dealer, and O'Hara assumes that readers will understand the social distinctions between a Cadillac, a LaSalle, a Buick, and a "Chevvy" (which O'Hara spelled with two V's). But beyond cars, the novel is full of other brand names, which O'Hara obviously expects to convey subtle social meanings to the reader:
- He reached over [in his car] and picked up the hat beside him.... The brim did not snap down in front. It was a Stetson, and Julian wore Herbert Johnson hats from Brooks Brothers."
- You would look at Mrs. Waldo Wallace Walker, dressed in a brown sweater with a narrow leather belt, and a tweed skirt from Mann and Dilks, and Scotch grain shoes with fringed tongues..."
O'Hara's books tended to push the limits of what was considered tolerable in a mainstream novel. His second, Butterfield 8, was notorious and was banned from importation into Australia until 1963. But Appointment in Samarra was controversial, too. Biographer Geoffrey Woolf quotes a Saturday Review article by , entitled "Mr. O'Hara and the Vulgar School," who criticized the book's sensuality as "nothing but infantilismthe erotic visions of a hobbledehoy behind the barn."
Most of O'Hara's descriptions are indirect: "There was the time Elinor Holloway... shinnied half way up the flagpole while five young gentlemen, standing at the foot of the pole, verified the suspicion that Elinor, who had not always lived in Gibbsville, was not naturally, or at least not entirely, a blonde." However, passages like the following were quite unusual for the time:
- She was wearing a dress that was cut in front so he could all but see her belly-button, but the material, the satin or whatever it was, it held close to her body so that when she stood up she only showed about a third of each breast. But when she was sitting down across the table from him she leaned forward with her elbows on the table and her chin in her hands, and that loosened the dress so that whenever she made a move he could see the nipples of her breasts. She saw him lookinghe couldn't help looking. And she smiled.