William J. Sharkey was a pickpocket, a con man, a politician, and a murderer, though whether or not that murder was an accident became the question at the center of a case that gripped New York for months. And then, he vanished. Sort of.
Research:

James Braid, Surgeon and Father of Hypnotism
43:36

Gladys Bentley
40:09

SYMHC Classics: Moms Mabley
33:10