- Dr. H.H. Holmes Dr. Henry Howard Holmes (May 16, 1861 - May 7, 1896) born under the name Herman Webster Mudgett was an American serial killer. He is known for having tortured and murdered perhaps as many as two-hundred people during the Chigaco Columbian World's Fair of 1893. He orchastrated his crimes in a large Hotel he had constructed in Chigaco which was nicknamed "The Murder Castle".