Former Pinkerton agent Booker DeWitt has been sent to rescue Elizabeth, a young woman imprisoned in Columbia since childhood. Booker develops a relationship with Elizabeth, augmenting his abilities with hers so the pair may escape from a city that is literally falling from the sky. DeWitt must learn to fight foes in high-speed Sky-Line battles, engage in combat both indoors and amongst the clouds, and harness the power of dozens of new weapons and abilities.