The London Vampire: The Charles Maddox Mysteries, Book 4

While investigating the origins of a mysterious donation to Oxford University, private detective Charles Maddox encounters the mysterious Baron Von Reisenberg, the subject of many rumours and macabre legends. In the light of day Maddox can find no evidence of anything sinister - until a series of disturbing incidents send him on a quest to expose whatever evil lurks in the Baron's castle.
After a terrifying encounter nearly costs him his sanity, Maddox returns home to find London besieged b...