Nate the Great and his dog Sludge try to track down Claude's missing Stegosaurus stamp.

When the Aldens agree to watch the house of a local author who has written a book about a vampire, they end up investigating activities that are suspiciously similar to those in his book.

The four Alden children, aged six to fourteen, volunteer at the new recycling center in town, and help uncover who is breaking in and making a mess each night.

When popular Lizzie Lovett goes missing, seventeen-year-old Hawthorne, a lonely misfit, finds herself becoming obsessed with solving the mystery. Bad things don't happen to popular girls like Lizzie Lovett-- until her disappearance became the one fascinating mystery the sleepy town of Griffin Mills has ever had. Hawthorn is convinced she'll turn up at any moment, and comes up with her own theory for Lizzie's disappearance. A theory way too absurd...

With a kindly new headmaster at Rookwood School, Scarlet and Ivy hope to focus on learning more about their mother but weird things start happening after a new ballet teacher arrives.

When Rosamond's birthday gift for Nate disappears from her sled, the boy detective decides to unravel the mystery.

Alice's father invites twelve-year-old Maisie and her dog Eddie to join Alice on a trip to the country, but the manor her father has rented seems to be haunted, terrifying Alice and putting Maisie's detecting skills to the test. Includes quizzes, activities, and more.

Before James grew up to be a ruthless, remorseless villain, he was a curious boy from Boston, with a penchant for trouble and an acid tongue. Thrown into a boarding school against his wishes, James winds up rooming with a most unlikely companion: a lanky British know-it-all named Sherlock Holmes ("Lock" to his friends). An heirloom Bible, donated by the Moriarty family more than a hundred years ago, has gone missing, and it doesn't take long for the...