Haunted Castle on Hallows Eve — Mary Pope Osborne

The castle looms dark against the light of the moon. Giant ravens circle in the sky. The wind whistles through the empty windows. Merlin the magician needs someone to find out what has happened. But who is brave enough to brush the cobwebs aside and go through the heavy doors? Who is smart enough to solve the mystery of how the castle became haunted and return it to its rightful owners? Merlin thinks he knows the answer to these questions -- Jack and Annie, two modern kids who have lots of experience with history, mystery, and magic! With the help of Teddy, a young sorcerer (and an old friend from an earlier adventure), Jack and Annie take on their second Merlin mission in the magical realm of Camelot.

Inspired by ancient legends and campfire ghost stories, Haunted Castle on Hallows Eve is a spooky and satisfying treat for readers all year round!