Indebted to the wrong people, and with his life on the line, hired gun Booker DeWitt has only one opportunity to wipe his slate clean. He must rescue Elizabeth, a mysterious girl imprisoned since childhood and locked up in the flying city of Columbia. Forced to trust one another, Booker and Elizabeth form a powerful bond during their daring escape. Together, they learn to harness an expanding arsenal of weapons and abilities, as they fight on zeppelins in the clouds, along high-speed Sky-Lines, and down in the streets of Columbia, all while surviving the threats of the air-city and uncovering its dark secret.