KC and her friend Marshall accompany KC's stepfather, the United States President, to remote Camp David, where they find clues that point to either ghostly or criminal activity.

While visiting their friend Wallis and her adopted daughter on Mount Desert Island, Maine, Josh, Dink, and Ruth Rose investigate why three white wolf cubs were stolen, and by whom.

Dink, Josh, and Ruth Rose investigate the theft of a great deal of money from the belly of a nearly life-size Tyrannosaurus Rex model that their friend, Jud Wheat, is using to raise money for a dinosaur museum.

When Dink, Josh, and Ruth Rose visit a dude ranch in Montana, they find themselves with another mystery to solve, this one involving the theft of money from the ranch's safe and of a large gold nugget that Josh had found.

"Mr. Paskey, owner of the Book Nook, plays an April Fools' Day prank on Dink, Josh, and Ruth Rose. They hatch a plan to get back at him, but then the bookstore is robbed--no joke! Can the kids track down the crook? Or will this April Fools' be an April fail?"--

Dink, Josh, and Ruth Rose are enjoying Halloween fun in Sleepy Hollow, New York, but when unplanned spooky things start happening, they invevestigate whether a real headless horseman might be to blame.