Throne of Glass

In a land where the king rules with an iron hand, an assassin is summoned to the castle. She comes not to kill the king, but to win her freedom. If she defeats twenty-three killers, thieves, and warriors in a competition, she is released from prison to serve as the king's champion. But Celaena Sardothien's fight for freedom becomes a fight for survival, and a desperate quest to root out the evil before it destroys her world.