Lost: One of Us

Jack, Kate, and Sayid are joyously welcomed back at the beach until everyone realizes Juliet is with them. Things are tense until suddenly Claire gets violently ill. Juliet tells Kate and Jack that she can help. Flashback into Juliet's life, we see her leaving her sister and being brought to the island by submarine. She is told she must help the people on the island - the women can not reproduce. After six months and no success, Juliet asks to go home. Ben reveals to her that he can cure her sisters cancer, but only if she stays. She does, and finds romance with Goodwin. But then Juliet discovers that Ben has cancer. If Ben has cancer, how can he have cured her sister? She calls him a liar. After the Oceanic plane crash, Ben takes Juliet to Mikhail's observation center and shows her live footage of her sister and healthy son playing in a park. Ben wants Juliet to stay and continue the work, saying that maybe there is a pregnant woman on the plane that crashed, and that they might be able to use her for a research subject. Back on the beach, Juliet is able to save Claire by giving her an injection that apparently Ethan had been giving her when they were using her as their "control" subject, and she was now going through withdrawal from. Everyone is happy when Claire is cured, and they are more accepting of having Juliet there. As Juliet sets up camp, we see another flashback featuring her and Ben, planning all the events that transpired last week in precise, cold detail, right up to Claire’s sickness and the device that will cause it. “I’ll see you next week,” Ben assures Juliet, who replies with a sly smile.