“United States of Secrets (Part Two)” - Trailer

How did the government come to spy on millions of Americans? More

How did the government come to spy on millions of Americans? In FRONTLINE’s “United States of Secrets,” a two-part series from Michael Kirk and Martin Smith premiering May 13 and 20, FRONTLINE tells the inside story of the U.S. government’s massive and controversial secret surveillance program—and the lengths they went to trying to keep it hidden from the public.

AIR DATE 5/11/14