The Government operates in secret. It denies basic facts to the public and its media. The stuff of Cold War novels. Or is it happening now?

Ten years after 9/11 there is a million-strong American workforce in 10,000 different locations. Untold billions are being spent on intelligence and national security - but it's all in secret.

Since 1983, Frontline has served as American public television's flagship public affairs series. It covers the most controversial and complex stories with credible thoughtful reporting and a powerful narrative - its aim for viewers being a good story, well told.

Top Secret America features Pulitzer Prize winning journalist Dana Priest and reveals the vast maze of clandestine government and private agencies which are "doing things you and I cannot know about. This world is growing up behind a black wall."

Behind this wall Priest examines a breathtaking list of secret actions, including drone strikes, domestic spying, black site prisons, alleged target assassinations and covert wars.

In this programme the Frontline team ask whether a decade of fighting terrorism has made America any safer.