Brother detectives Frank and Joe search a concealed castle for clues to help them find a missing comic book in the nineteenth book in the thrilling Hardy Boys Adventures series.

Frank and Joe have been hanging out at Sir Robert’s Comic Kingdom, the neighborhood comic and gaming shop, and got the unique invite to the year’s Halloween costume ball at Bayport’s only castle. Sir Robert plans to use the special day to unveil his most prized possession, a brilliant rare comic that’s rumored to contain a map to buried treasure.

Sir Robert agrees to show his store regulars—who now consist of Frank and Joe—a sneak preview of the comic before the party. However when he would go to unlock the fireproof casing, he finds the book is gone.

It will take most of Frank and Joe’s lately acquired LARPing abilities to resolve this case. Anything can occur inside a castle full of dungeons and deception. Can the Hardy boys keep up?