The collapse of the Victoria Embankment uncovers a passage to an unknown realm beneath the city. Langdon St. Ives sets out to explore it, not knowing that a brilliant and wealthy psychopathic murderer is working to keep the underworld's secrets hidden for reasons of his own.
St. Ives and his stalwart friends investigate a string of ghastly crimes: the gruesome death of a witch, the kidnapping of a blind, psychic girl, and the grim horrors of a secret hospital where experiments in medical electricity and the development of human, vampiric fungi, serve the strange, murderous ends of perhaps St. Ives's most dangerous nemesis yet.
The distances that stretched away on three sides of the great cavern lay in perpetual half-darkness, with absolute darkness above, the invisible ceiling of the cavern supported by limestone columns as...