Throughout human history, there have been sudden and dramatic leaps in our evolution that simply cannot be explained by Darwinian theory. Ancient Astronaut theorists propose that the "missing link" is extraterrestrial intervention. The evidence may be found in our proto-human past, the key moments in our development, and the extraordinary changes witnessed in new generations being born. Could humanity be overdue for the next upgrade? And if so, what might be in store for the human race?