After two decades, the LAPD says it has solved the "Grim Sleeper" serial killings, culminating in the arrest of a suspect on Wednesday. Police credit the use of a cutting-edge technology -- "familial search." Reporter Maura Dolan explains how it all works. Spies in our midst are apparently not just the thing of novels and movies. Friday afternoon, the Department of Justice confirmed that the United States and Russia exchanged 10 spies arrested in the U.S. for four convicted in Russia in a carefully crafted diplomatic maneuver. Ken Dilanian in our Washington bureau offers some context on where the real action is in espionage.