Early on the evening of Oct. 28, 1893, 25-year-old Patrick Prendergast came calling at the home of Mayor Carter Harrison of Chicago. The maid asked him to wait in the foyer while she fetched His Honor. But he ran past her and headed down the hall. The commotion drew Harrison out of his library. There was a confrontation. Words were exchanged. Then Prendergast pulled out a revolver and shot the mayor dead.