The earth has existed quietly for 4.6 Billion years, and human history is only a glimpse in comparison. In the long river of time, we have refined various economies, cultures, and politics, and built the tower of today's scientific and technological civilization.
But who would have thought that before our group of humans was born, another group of humans had set foot on this land, and they also had a unique economy, culture, and politics.
How are they different from us? And why did it disappear without leaving any trace? What secrets are hidden in our world? Does the world really work as we know it?
