For an eighth grader, Molly Williams has more than her fair share of problems. Her father has just died in a car accident, and her mother has become a withdrawn, quiet version of herself.

Molly doesn't want to be seen as 'Miss Difficulty Overcome' ; she wants to make herself known to the kids at school for something other than her father's death. So she decides to join the baseball team. The boys' baseball team. Her father taught her how to throw a knuckleball, and Molly hopes it's enough to impress her coaches as well as her new teammates.

Over the course of one baseball season, Molly must figure out how to redefine her relationships to things she loves, loved, and might love: her mother; her brilliant best friend, Celia; her father; her enigmatic and artistic teammate, Lonnie; and of course, baseball.