Title: The secret of the cellars
Description: Originally published in 1964, bestselling author Carolyn Hart’s young adult mystery novel will appeal to everyone who loved the adventures of Nancy Drew. 

Sally Warren, Tish Howard, and Tish’s brother, Mike, are three high-energy teens in a sleepy academic town that houses a top tier University. When a stranger buys a decrepit Victorian mansion because of its rumored secret cellar, and a graduate student demonstrates a peculiar interest in the basement, Mike, Sally, and Tish are on the case! But what starts as an imaginative game turns into very real danger, and the teens will have to use their wits and enthusiasm to survive a series of high stakes adventures that have them uncovering secret compartments, FBI identities, and classified government secrets!