Serial killer suspect went unnoticed

He lived in the shadows, emerging just long enough to be caught on videotape, a grainy predawn image as he shot Patricia McDermott in cold blood on a Center City street.
In that May 17 footage, McDermott, 48, an Elkins Park mother of two, is walking down Ninth Street near Market, her hands in her pockets, heading toward her job as a radiology technician at Pennsylvania Hospital. >>>ReadOn