"Cassidy's Run is the story of one of the best-kept secrets of the Cold War - an espionage operation mounted by Washington against the Soviet Union that ran for twenty-three years. At the highest levels of the government, its code name was Operation SHOCKER.". "Lured by a double agent working for the United States, ten Russian spies, including a professor at the University of Minnesota, his wife, and a classic "sleeper" spy in New York City, were sent by Moscow to penetrate America's secrets. Two FBI agents were killed, and secret formulas were passed to the Russians in a dangerous ploy that could have spurred Moscow to create the world's most powerful nerve gas.". "Cassidy's Run tells this extraordinary true story for the first time, following a trail that leads from Washington to Moscow, with detours to Florida, Minnesota, and Mexico." "More than a cloak-and-dagger tale, Cassidy's Run is the story of one ordinary man, Sergeant Joe Cassidy, not trained as a spy, who suddenly found himself the FBI's secret weapon in a dangerous clandestine war."--BOOK JACKET.