Dink, Josh, and Ruth Rose investigate a mysterious man in black who Josh believes is a vampire.

Dink and his friends unearth the mysterious truth behind the envelopes incorrectly delivered to his house.

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.

When Dink, Josh, and Ruth Rose visit Plymouth, Massachusetts, for Thanksgiving, they uncover a mystery that dates back to the landing of the Pilgrims.

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. W is for Wolf. ... Dink, Josh, and Ruth Rose are thrilled to visit Wallis Wallace at her new cabin in the Maine wilderness. On their very first day, they glimpse a white wolf and her babies on a cliff. But soon after the kids spy the wolf family, the pups are wolf-napped!...

While learning detective skills at summer camp, Dink, Josh, and Ruth Rose undercover a real mystery involving stolen paintings. Includes a hidden message.

When KC and Marshall see lights flickering at night in the Washington Monument, their investigation turns up a monkey, a hole in one of the monument stones, and a hundred-year-old mystery.

"It's sleepover night at the children's museum. Dink, Josh, and Ruth Rose can't wait to see the museum's colossal fossil--a giant Spinosaurus skeleton--and tour the exhibits long past closing time. But later, they wake to a terrible crash! Is the dinosaur fossil damaged? Or is there another big problem at the museum?"--

KC and Marshall take a tour of the Bureau of Engraving and Printing, and when they discover that someone has been stealing bricks of newly printed money, they resolve to find the thief.

While visiting Thomas Jefferson's home, Monticello, presidential stepdaughter KC Corcoran and her friend Marshall investigate the theft of a box of toy horses given to Jefferson by his grandchildren.