Frank Geyer (July 28, 1853 – October 4, 1918) was an American detective from Philadelphia, Pennsylvania, best known for arresting H H Holmes, one of the first known serial killers of the United States. Geyer was a member of the famed Pinkerton detective agency and caught Holmes while working on what would be known as the Holmes-Pitezel Case. He published the story in his book, The Holmes-Pitezel Case: a history of the greatest crime of the century and of the search for the missing Pitezel children. In the 2003 bestselling book The Devil in the White City Frank Geyer is described as a "big man with a pleasant, earnest face". His wife and daughter were killed in a fire a short time before he started investigating the Holmes case. Son of Reuben K. Geyer and Camilla Buck, Frank Geyer died at the age of 65 due to complications from heart disease and his funeral was attended by hundreds of policemen and detectives.
Bio from Wikipedia - See more on en.wikipedia.org Text under CC-BY-SA license