Frank and Joe Hardy are determined to stop a group of pranksters before their mean-spirited practical jokes and vandalism become more destructive and dangerous.

Someone is spray-painting graffiti all over Cedar Valley and it is up to fifth-grader Nolan Byrd, also known as Shredderman, to expose the vandal.

Joe and Frank Hardy win a contest to be handlers for a Green Crawler balloon in the annual fall festival, but when the balloon is sabotaged the day before the parade, the brothers must investigate.

When Binky is accused of vandalizing school property, Buster and Fern test their detective skills to find the real culprit.

The Alden siblings volunteer at the local recycling center, where they find plenty of things that can be reused, but when the center is vandalized, they must investigate to solve the mystery.

After the neighborhood basketball court is vandalized, Ziggy and his friends decide to form a club called the Black Dinosaurs and build their clubhouse in Ziggy's backyard.

"In this new collection of mysteries, everyone's favorite poet detective is back in action. When a prankster tangles all the school jump ropes into knots and gym is canceled, Marty pins down the culprit. When five machines are mysteriously found broken at the arcade, Marty jumps on the case. And when Mom's phone goes missing after a trip to the mall, Marty races against the clock to track it down before dinner. But can he still manage to make up rhymes...