In this companion novel to Midsummer's Mayhem, math and baseball combine with savory snacks to cause confusion and calamity in the town of Comity.

Twelve-year-old Trish can solve tough math problems and throw a mean fastball. But because of her mom's new job, she's now facing a summer trying to make friends all over again in a new town. That isn't an easy thing to do, and her mom is too busy to notice how miserable she is.

But at her first baseball practice, Trish realizes one of her teammates is Ben, the sixth-grade math prodigy she beat in the spring Math Puzzler Championships. Everyone around them seems to think that with their math talent and love of baseball, it's only logical that Trish and Ben become friends, but Ben makes it clear he still hasn't gotten over that loss and can't stand her. To make matters worse, their team can't win a single game. But then they meet Rob, an older kid who smacks home runs without breaking a sweat. Rob tells them about his family's store, which sells unusual snacks that will make them better ballplayers. Trish is dubious, but she's willing to try almost anything to help the team.

When a mysterious booklet of math puzzles claiming to reveal the ultimate answer arrives in her mailbox, Trish and Ben start to get closer and solve the puzzles together. Ben starts getting hits, and their team becomes unstoppable. Trish is happy to keep riding the wave of good luck ... until they get to a puzzle they can't solve, with tragic consequences. Can they find the answer to this ultimate puzzle, or will they strike out when it counts the most?