When the story begins, a man named Erwin Martin, who never smokes, is buying cigarettes. Mr. Martin works for a company called F & S, where he is in charge of the filing department. Mr. Martin has already been contemplating—and planning—the murder of a coworker for over a week. Two years prior, a woman named Ulgine Barrows joined F & S, where she quickly proposed changes to the department—changes that Mr. Martin finds intolerable.

Later, as he sits in his apartment drinking a glass of milk, Mr. Martin imagines Mrs. Barrows’s offenses against him and the department as if he were a prosecuting attorney in court: He finds her guilty of inefficiency, irritating behavior, and destroying his department. Maintaining his imaginary posture of legal counsel, he reviews the evidence. He remembers with bitterness Mrs. Barrows’s professional (and, he believes, unwarranted) ascent, a story he gleaned through office gossip: Mrs. Barrows met their boss, Mr. Fitweiler, at a party and used some “monstrous magic” to charm him. She was hired a week later. In addition to the insult of the usurpation, Mrs. Barrows has other qualities that Mr. Martin finds insufferable; she is given to unusual metaphorical turns of phrase and folksy sayings like, “Are you sitting in the catbird seat?” (1) that she stole from a baseball announcer, for example. She is loud, and Mr. Martin often describes her manner of speech as “braying.” Finally, after two years of wearing down his patience, Mrs. Barrows committed the unpardonable misdeed of asking Mr. Martin if all of his many filing cabinets were necessary. Quietly outraged to his core, Mr. Martin decided his coworker needed to be erased, as one might erase a clerical error. Now, as he sits in his apartment, milk glass still in hand, his courtroom reverie concludes: He demands the death penalty for the defendant.

The next day, Mr. Martin goes to Mrs. Barrows’s apartment to pay her a surprise visit. While she is making drinks for them, he searches the living room for potential murder weapons—to no avail. Mr. Martin forms a new plan and immediately slips into a false persona; when Mrs. Barrows offers him the drink, he takes it, even though he never drinks anything stronger than milk or ginger ale (and his indulgence surprises Mrs. Barrows, who is aware of his reputation and customary abstinence). He toasts to their boss, Mr. Fitweiler, and then insults him. Mrs. Barrows bristles at the disrespect. He continues slandering his boss and hints that he will murder him. Alarmed, Mrs. Barrows asks him if he is on drugs. Escalating his masquerade, Mr. Martin says that he uses heroin and that he will be heavily under the influence when he murders Mr. Fitweiler. Mrs. Barrows shouts at him to leave, and he goes home—but only after turning back to her to say mockingly, “I’m sitting in the catbird seat” (4) and sticking out his tongue. When he returns to his apartment, he enjoys not one but two self-congratulatory glasses of milk.

The next day, Mrs. Barrows reports him to Fitweiler, who summons Mr. Martin to his office. He asks if it’s true that Mr. Martin has never drunk or smoked. He then says that Mrs. Barrows has had a “severe breakdown” involving a “persecution complex” with hallucinations and has accused Mr. Martin of behaving inappropriately. Fitweiler has recommended that she see a doctor and now tells Mr. Martin that Mrs. Barrows’s time at the company has come to an end. Mr. Martin says he is “dreadfully sorry” to hear this.

Mrs. Barrows bursts in and demands to know if Mr. Martin is denying her accusations. She accuses him of setting her up. Two men named Stockton and Fishbein see her out. Fitweiler dismisses Mr. Martin and asks him to forget about the incident. Mr. Martin says he will and returns to his department. He has killed Mrs. Barrows’s career at R & S, even though he spared her life.