Parts of the story take place in the Laurentian Mountains in the resort town of Sainte-Agathe-des-Monts and surrounding areas.

The novel focuses on the young life of Duddy Kravitz, a poor Jewish boy raised in Montreal, Quebec.

Their relationship is strained: Uncle Benjy, a wealthy clothing manufacturer with socialist sympathies, has always favored Duddy's brother Lennie, who wants to become a doctor.

The two travel to New York City, but Duddy fails to secure assistance from the "Boy Wonder", who sees him as a naive upstart and uses him to ferry a package of heroin across the Canada-U.S. border.

Back in Montreal, Duddy rents an apartment and an office for himself and Yvette and begins buying the plots of land around the lake.

Uncle Benjy's death acts as a trigger for Duddy, who has a nervous breakdown and refuses to leave his room for a week.

He loses his clients and must declare bankruptcy and surrender all his possessions to the government (except for the land, which was in Yvette's name due to Duddy being considered a minor).

But in the Montreal St. Urbain Street joint where his taxi-driving father spends most of his time entertaining regulars with stories, someone recognizes Duddy as the guy who has acquired all of the land surrounding the lake in the Laurentians, and when Duddy, ordering servings for everyone while he has no cash to pay, gestures to his father, he is answered by the patron, "That's all right, sir.

Aging in more-or-less real time, Duddy Kravitz makes brief, comic appearances in both St. Urbain's Horseman and Barney's Version (1997).