DATELINE NBC "Dennis Murphy"

Dennis Murphy, winner of four national Emmys for excellence in news reporting, has covered stories for NBC News from more than 50 countries. As a regular contributor toNBC Nightly News with Tom Brokaw andToday, his assignments have given him a front-row seat for some of the biggest stories of the last two decades—from wars in the Persian Gulf and Central America to the collapse of the Soviet Empire and the Berlin Wall, and most recently, the war on terror in Afghanistan.   Friday, June 1 at 9p/8c An Iowa mother, home alone with her three children, fatally shoots a local teenager who she claims attacked her. When investigators discover the identity of the teen, they wonder if the mother has something to hide. Dennis Murphy reports.