The Black World of UFOs: Exempt from Disclosure

Was there a government UFO cover-up? What about those highly sensitive Defense Intelligence Agency (DIA) documents dealing with reverse engineering and who sent them? What is the Crystal Rectangle mentioned by Helms and reported in those DIA documents? What happened on the Space Shuttle and ISS with this Crystal Rectangle before the Columbia disaster? Why is Los Alamos having so many problems with reverse-engineering specifically the propulsion system and materials? With 75 unique illustrations the story is told from many different perspectives.