James May always wanted to be an astronaut. Now, 40 years after the first Apollo landings, he gets a chance to fly to the edge of space in a U2 spy plane. But first he has to undergo three gruelling days of training with the US Air Force and learn to use a space suit to stay alive in air so thin it can kill in an instant. He discovers that during the flight there are only two people higher than him, and they are both real astronauts on the International Space Station.