The year is 1912, deep in debt, ex-Pinkerton agent Booker DeWitt is sent to the mysterious flying city of Columbia to find and retrieve a young woman imprisoned in a tower since birth - Elizabeth and to "Bring us the girl and wipe away the debt". However, almost as soon as Booker arrives, he finds that Columbia and its people are not quite what they seem, and all too soon science, religion, morality, family and life all clash and spiral down into utter chaos, with Booker and Elizabeth as unlikely partners in the midst of all the action.