When a wealthy dog spots a ghostly figure haunting her castle in the Catpathian Mountains, she comes to Bones and Catson for help. Bones is convinced there’s no such things as ghosts ... but even he’s at a loss to explain the creepy sounds and strange goings-on that he and Catson encounter after a night in the crumbling castle. Things get even more spooky when Bones is suddenly called back to London, leaving Catson to crack the case on her own. Can Catson unmask the ghost and escape the haunted castle in one piece?

The fourth book in Buster’s Sherlock Bones mystery fiction series features 28 puzzles – including spot-the-differences, number chains and tangled line games – that are woven into the action, so the reader feels immersed in the exciting detective plot. Told across 15 chapters, this thrilling story is perfect for middle-grade readers.