First, food starts disappearing from Miss Nellie's cafe. Then lumber walks away from Mr. Henley's hardware store. Always ready to solve a mystery, the Two Amigos Detectives, Marco Garcia and Jake Bigsley, set out to catch the odd thief. It appears to be an open-and-shut case. All the clues point to Mr. Klem, whose large family is poor by most standards. But Marco, friends with one of the Klem girls, can't bring himself to accuse the head of such a happy family. When a surprise comes to Tall Pines, however, the case takes a sudden turn. In the days that follow, a revelation rocks the town and Marco's understanding of what it means to be rich is challenged as he and Jake work to solve the crazy case of the Peanut-Butter Burglar.