Forty years ago, the national mood of political unrest and protest filtered into the United States prison system. And on September 9, 1971, and prisoners at New York's Attica Correctional Facility seized control of the prison. The prisoners took hostages and demanded better living conditions. William Kunstler was called in to negotiate on behalf of the prisoners. After three days of negotiations, armed troops amassed outside the prison gates. What happened next was one of the bloodiest encounters between Americans since the Civil War.