This Side of Paradise chronicles the coming of age of Amory Blaine, born to a wealthy midwestern family. It begins with Amory as a spoiled youth, doted on by his eccentric mother Beatrice. It follows him as he attends preparatory school and Princeton, and then briefly attempts but quickly abandons at a career in advertising. His service in World War I is mentioned but mostly glossed over. Covered in much more detail are his various romances:

Soon-to-be high school junior David Harper hates his family’s move to the country. There’s nothing to do, and he misses his friends in the city. But he doesn’t have a choice. His mother’s job is in Mason County now, so David and his mom are too, and he has to make the best of it.

At first, the only redeeming feature of David’s new home is the swimming hole across the field from his house. Then David meets Benjamin Killinger, and

Redlaw is a teacher of chemistry who often broods over wrongs done him and grief from his past.
He is haunted by a spirit, who is not so much a ghost as Redlaw's phantom twin and is "an awful likeness of himself...with his features, and his bright eyes, and his grizzled hair, and dressed in the gloomy shadow of his dress..." This specter appears and proposes to Redlaw that he can allow him to "forget the sorrow, wrong, and trouble you have