The Slype is a dark passage, reputedly haunted, adjoining the ancient cathedral of Dullchester, and it plays a central role in this thrilling mystery. As the story opens, this sleepy cathedral city has a sinister visitor whose ominous pastime consists of cutting paper silhouettes depicting a corpse hanging from a gibbet. After his arrival, a series of terrifying events ensues: ghostly screams are heard to emanate from the Slype, and the town's residents begin disappearing one by one, inexplicably and without a trace. Young Daniel Dyke, Sergeant Wurren, and Inspector Macauley of Scotland Yard will have to join forces to unravel this deadly mystery and uncover a centuries-old secret ... before it's too late!