The Hustlers start a swap shop as a money-making project, but have to deal with the disappearance of Ginny's Great-Aunt Betsy's heirloom silver candlesticks, and along the way tackle a jewel thief.

The Hustlers still have the swap shop, but now it is old Mrs. Arnold's pendant that is missing. Ginny finds that the plot is not just about a pendant, but a scheming woman's plan to take over all of Mrs. Arnold's estate.

The Hustlers have sold the swap shop to Joe Dakor, and their new project is a snack barn as a hangout for young people.

The Hustlers latest project is a subscription lending library. Mystery develops as someone keeps trying to steal a popular novel.

The Hustlers are having a used book sale at their lending library when a rare and valuable book of Mrs. Arnold's is mistakenly donated. When Mrs. Arnold attempts to recover the book, all the Hustlers are certain they did not sell it, but it cannot be found. Ginny tries to solve the mystery of the missing book, while other mysteries abound: the identity of a bitter young woman who moves to Harristown and all the pranks and confusion at the lending library. The whole time, Ginny is trying to organize a radio book-chat for teenagers that the local radio station asked her to do.