When Mr. Hardy disappears while investigating a mystery surrounding a vacant house rumored to be either haunted or an abode for criminals, Joe and Frank search for the truth.

A rare Chinese vase is stolen from a pottery shop. Nancy and the owner of the shop feel that locating "the leaning chimney" will provide the clue to the vase and other stolen articles.

Nancy encounters a mysterious saleswoman in a perfume shop, a curious man on the train, and then finds herself trying to decipher a strange code.

Josh and his two friends look for the person who stole a peregrine falcon from its nest.

Nancy finds herself in danger when she tries to solve the mystery of an old inn which seems to be jinxed.

Nick and his friend Marta decide to investigate when a mysterious fire starts near a Florida wildlife preserve and an unpopular teacher goes missing.

Caroline Verlaine comes to the Stacy estate investigating her sister Roma's sudden disappearance. Caroline finds the secret of the ruins that cost her sister her life, also threatening her.

In the middle of the night, Anna hears Acorn's whinny in the Crandal paddock. There is a fire in Dr. Crandal's animal clinic. All the animals are in danger!

When the guests of the Shangri-La Hotel are scared away by a white-haired female ghost, Dink and his friends investigate the mystery.