From the Presidents famous Oval Office in The White House, to the secretive operations of the clandestine Freemasons fraternity, discover a layer of intrigue hidden just beneath the surface of the worlds most powerful nation. In this revealing 10-part series from HISTORY, go behind closed doors to uncover the closely-guarded secrets and enduring mysteries of some of Americas iconic institutions, including the Pentagon, Area 51, West Point Military Academy, the Federal Bureau of Investigation, Fort Knox and many more.