The spy in the bleachers / Warner, Gertrude Chandler

The Aldens are thrilled to be helping out at Cogwheel Stadium as the Clayton Cogs try to win the pennant, but when the children realize someone has stolen the team's pitching signals and given them to the other team, they set out to find the spy before he ruins the team's chance at victory.

The Aldens help out at a minor league stadium and investigate when it appears someone in the ballpark is stealing the home team pitcher's signals and relaying them to the batters of the other team.

When it becomes clear someone in Cogwheel Stadium is stealing the Cogs' pitcher's signals and giving them to the other team's batters, the Aldens must find out who is doing the spying.