Beginning in Ethiopia, Professor Brian Cox discovers how the universe played a key role in our ascent from apeman to spaceman by driving the expansion of our brains. But big brains alone did not get us to space. To reveal what did, Brian heads out of Africa to the ancient city of Petra in Jordan, where he unpicks the next part of our story - the birth of civilization - and then on to Kazakhstan, where he witnesses the return of astronauts from space and explains what took us from civilization to the stars.