The Calendar Club Mysteries follow the investigations of a team of elementary-school-aged detectives as they solve mysteries all over their small town. The Calendar Club is led by second-grade sleuth Casey Calendar along with her best friends Leon Spector, a geography whiz, and list-maker Dottie Plum. Each book tackles a seasonal mystery, from a town full of missing pumpkins to a summer vacation postponed to catch garden vandals. Calendar Club Mysteries have been an enormous success since the initial release of The Case of the Missing Pumpkins in 2004.