The day humanity finally discovered how to save the world began the countdown to their own destruction. A thousand years ago, the human race was almost wiped out. Now Earth has become a dangerous place to live in. In the remnants of what was once a thriving country stands Calypso, the last city on Earth. Twice a year, every sixteen-year-old is taken from their families to face numerous trials that would prove themselves worthy of continuing life in the city. Prudence Archer knows she must do whatever it takes to survive all the tests for failure only means one thing: exile.