Might an examination of Leonardo Da Vinci's masterful paintings, highly technical hand-drawn sketches, and private journals reveal knowledge of otherworldly technology and extraterrestrial beings?

Angkor Wat, Cambodia, is the world's largest ancient religious temple. Within its megalithic ruins, researches have discovered a depiction of a species of dinosaur--a stegosaurus. But how could the ancients have had knowledge of animals that mainstream science says died out millions of years ago? Why are dinosaurs extinct? Did an alien race of beings kill off the dinosaurs to make room for humankind?