A Separate Peace is the story of Gene Forrester. He is a quiet, intellectual student at Devon School and his best friend and roommate is the polar opposite. Whereas Gene can keep up as an athlete, his real strength resides with academics. His roommate can be described as everything else.

Finny is charming, self-confident, athletic, and a daredevil without ever being arrogant. It is as if he knows himself to be extraordinary, but wears it like someone might wear a jacket. He doesn't have any inclination to best or defeat anyone. He merely enjoys competing with himself, relishing the idea that others might join in his long list of personal challenges.

At the opening, it seems Gene admires these qualities. But by the fourth chapter, he become conscious of his secret and growing resentment toward Finny. He is weary of Finny being the natural leader, the better athlete, and the more charismatic student who can talk his way out of anything.

At the dark heart of A Separate Peace, identity and transformation become pivotal themes. They are not just important for these two boys but several other classmates as well. As a summer of innocence metamorphoses into the winter of discontent, Elwin "Leper" Lepellier becomes the boy to enlist in the military and Brinker Hadley finds room to assert himself as a new leader at Devon.