Bioshock 2 is set in the city of Rapture in alternative history of 1968, eight years after the events of BioShock. The protagonist and player-controlled character is Subject Delta, a being that has had its organs and skin grafted into an atmospheric diving suit. Among the first of the Big Daddies, the player-controlled Big Daddy reactivates with no recollection of the past decade's events, and wanders the city in a vain attempt to relocate the Little Sister that he was paired with. When it becomes obvious that Rapture's leader Sofia Lamb will become responsible for the city's destruction, Subject Delta attempts to overthrow Lamb and her army of Big Sisters.