Eleanor Lamb is a major character in the story of BioShock 2. During the game's opening minutes, set during the era of the original BioShock, Eleanor is a Little Sister that has been bonded with the Big Daddy Subject Delta. Because of the nature of the bonding shared between alpha-series Big Daddies such as Delta and Little Sisters, they see each other as father and daughter despite not being directly blood related. Rather, Eleanor is the daughter of Sofia Lamb, rival of Andrew Ryan.
Upon being forced to part with Subject Delta after Sofia Lamb forced him to shoot himself in the head, Eleanor becomes a rebel of Rapture. Sofia, fearing that she would bring the city down, put her in a medically induced coma. However, through her bond with Delta, Eleanor was able to reawaken him and guide him to her. The choices the player makes along the way influence how she is portrayed in the end. In particular, Eleanor's personality and ultimately the game's ending are determined by how the player treats the Little Sisters and the NPC's Grace Holloway, Gilbert Alexander, and Stanley Poole. Eleanor is very attached to her father Delta no matter which ending the player gets. She is portrayed as either loving, caring, and virtuous, or hateful, angry, and self-centered. Either way, she supports the player with various gifts and hints throughout the game.
If the player saves all of the Little Sisters, she is taught the virtues of mercy and freedom. The good ending shows Eleanor lovingly extracting Delta's ADAM as he lays dying so that he may become a part of her. She then states, "Now you will be with me always father, watching, guiding, and when I need you; you will be there on my shoulder, whispering." After she says this a little sister hands her a Subject Delta Big Daddy doll that she carried around while she was a little sister. She shows the group of saved sisters and drops the doll into the ocean, signifying Delta's freedom.
If the player harvests at least one but not all of the Little Sisters, the player will be given a choice in the game's ending. As Eleanor moves to extract Delta's ADAM, Delta may either choose to stop her before dying, demonstrating freedom in his final moments, or submitting to Eleanor's extraction of his ADAM.
If the player saves all of the Little Sisters, but kills people such as Grace Holloway or Alexander Gill, they receive the "Evil" Ending, in which Eleanor says "You taught me that my own survival, my happiness, is all that matters, nothing else is real, you made me see that my survival, is the most important thing." After they reach the surface she injects Delta with the same needle and says."You may not have wanted me father, but you defined me. You chose to survive, no matter what the cost, and I will not let your instincts go to waste. The Rapture dream is over, and in waking I am reborn. You'll always be with me father, your memories, your drives. When I need you, you'll be on my shoulder whispering over my shoulder. There is no name for what I am, but the world is about to change. And with your help, they will never see me coming."