Necropolis

"Set in an alternate Victorian London, where Sherlock Holmes and Dr. Watson are not just fictional characters, Basil Copper's Necropolis (1980) is a tale of mystery and intrigue worthy of Arthur Conan Doyle or Wilkie Collins. Private detective Clyde Beatty, a rival of the great Holmes, has been hired by the lovely Angela Meredith to inquire into her father's suspicious death. As Beatty's investigation unfolds, the danger intensifies: more murders ensue, and attempts are made on his life. It is clear there is more to Mr. Meredith's death than meets the eye, and it may have something to do with the brazen robbery of a fortune in gold bullion. The clues lead Beatty to the eerie Brookwood Cemetery, where fatal secrets lie hidden in the catacombs beneath a city of the dead."--Goodreads