4500 years ago, a civilization that knew nothing of iron tools, wheels or pulleys built the Great Pyramid of Khufu. For centuries, its construction remained an unsolved mystery. But recently, a French architect disclosed a revolutionary theory: the pyramid may have been built from the inside out. Using the most advanced scientific 3D technology, Jean Pierre Houdin tested and re-enacted the construction of Khufu’s tomb. He believes that an internal spiral ramp is still there…. just waiting to be found.