Teenage detectives Frank and Joe Hardy investigate a supposedly haunted house reported to be the hangout of criminals.

After a dying criminal confesses that his loot has been stashed "in the tower", the Hardy boys make an astonishing discovery.,

Fifth-grade sleuth Cam Jansen uses her photographic memory to solve a monkey smuggling mystery at the city zoo.

Dink Duncan and his two friends investigate the apparent kidnapping of famous mystery author Wallis Wallace. A is for author ... Dink writes to his favorite author, mystery writer Wallis Wallace, and invites him to visit Green Lawn. To Dink's amazement, Wallace says he'll come! But when the big day arrives, Wallace is nowhere to be found. The police think he just missed his plane, but Dink suspects foul play. It's up to Dink and his two best friends,...

Nancy Drew becomes involved in a double mystery concerning a haunted bridge and jewel thieves.

When cats begin to mysteriously disappear in Santa Martina, thirteen-year-old friends Sammy and Holly start snooping around town to find out what is happening.

While helping the police find the owner of a mysterious house with a crooked staircase and an unpredictable robot, Nancy Drew, girl detective, also helps capture a swindler.

Nate the Great takes on his first night case and tries to solve the mystery of the garbage snatcher.

Encyclopedia Brown, boy detective extraordinaire, solves ten new cases, including "The Case of the Miracle Pill," "The Case of Nemo's Tuba," "The Case of the Lawn Mower Races," and "The Case of the Air Guitar." Solutions provided at the end of each chapter.

Dink and his two friends help Lucky find the culprit who stole Lucky's winning lottery ticket.