Clyde Griffiths is raised by poor and devoutly religious parents to help in their street missionary work. As a young man, Clyde must, to help support his family, take menial jobs as a soda jerk, then a bellhop at a prestigious Kansas City hotel. There, his more sophisticated colleagues introduce him to bouts of social drinking and sex with prostitutes.
Enjoying his new lifestyle, Clyde becomes infatuated with manipulative Hortense Briggs, who manipulates him into buying her expensive gifts. When Clyde learns Hortense goes out with other men, he becomes jealous. Nevertheless, he would rather spend money on her than to help his sister, who had eloped, only to end up pregnant and abandoned by her lover.
Clyde's life changes dramatically when his friend Sparser, driving Clyde, Hortense, and other friends back from a secluded rendezvous in the country in his boss's car, used without permission, hits a little girl and kills her. Fleeing from the police at high speed, Sparser crashes the car. Everyone but Sparser and his partner flee the scene of the crime. Clyde leaves Kansas City, fearing prosecution as an accessory to Sparser's crimes.
While working as a bellboy at an exclusive club in Chicago, he meets his wealthy uncle Samuel Griffiths, the owner of a shirt-collar factory in the fictional city of Lycurgus, New York. Samuel, feeling guilt for neglecting his poor relations, offers Clyde a menial job at the factory. After that, he promotes Clyde to a minor supervisory role.
Samuel Griffiths's son Gilbert, Clyde's immediate supervisor, warns Clyde that as a manager, he should not consort with women working under his supervision. At the same time the Griffithses pay Clyde little attention socially. As Clyde has no close friends in Lycurgus, he becomes lonely. Emotionally vulnerable, Clyde is drawn to Roberta Alden, a poor and innocent farm girl working in his shop, who falls in love with him. Clyde secretly courts Roberta, ultimately getting her pregnant.
At the same time, elegant young socialite Sondra Finchley, daughter of another Lycurgus factory owner, takes an interest in Clyde despite his cousin Gilbert's efforts to keep them apart. Clyde's engaging manner makes him popular among the young smart set of Lycurgus; he and Sondra become close, and he courts her while neglecting Roberta. Roberta expects Clyde to marry her to avert the shame of an unwed pregnancy, but Clyde now dreams instead of marrying Sondra.
Having failed to procure an abortion for Roberta, Clyde gives her no more than desultory help with living expenses while his relationship with Sondra matures. When Roberta threatens to reveal her relationship with Clyde unless he marries her, he plans to murder her by drowning while they go boating. He had read a local newspaper report of a boating accident.
Clyde takes Roberta out in a canoe on the fictional Big Bittern Lake (modeled on Big Moose Lake, New York) in the Adirondacks, and rows to a secluded bay. He freezes. Sensing something wrong, Roberta moves toward him, and he unintentionally strikes her in the face with a camera, stunning her and accidentally capsizing the boat. Roberta, unable to swim, drowns, while Clyde, unwilling to save her, swims to shore. The narrative implies that the blow was accidental, but the trail of circumstantial evidence left by the panicky and guilt-ridden Clyde points to murder.
The local authorities are eager to convict Clyde, to the point of manufacturing additional evidence against him, and he repeatedly incriminates himself with his confused and contradictory testimony. Despite a vigorous (and untruthful) defense by two lawyers hired by his uncle, Clyde is convicted, sentenced to death, and after an appeal is denied, he is executed by electric chair.
