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 by an elusive murderer branded the Vampire. There's little doubt in Maddox's mind who's responsible – and it's up to him to end the monstrous affair before more innocent blood is spilled…
“Tense, terrific.” - Ian Rankin
“Another tour de force with a striking finale.” - Kirkus Reviews starred review
“Another sterling entry in this imaginative series.” - Booklist
“Compulsively readable, suspenseful, and dark... unsettling in the best way.” - Historical Novels Review