Juliet wants to warn Jack that the freighter people are not who they say they are over the walkie-talkie, but doesn't argue much when they decide to find him and tell him in person.
Juliet is concerned that Jack and Kate are not back to the beach, so she and Sayid get guns, go to the cockpit (where they knew Jack and Kate had left from), and track them. They help Jack to get control of Miles and Daniel. They all go to the pilot and helicopter. As Juliet fixes up Frank, he asks her name and realizes that she was not on the manifest. He tells Miles that Juliet is a native and Miles immediately asks where Ben is.
Jack asks Juliet how long it would take to get to the beach and back and when she says two hours, Jack asks if she'll go get Desmond. She does.
Juliet knows that there is something going on regarding the helicopter because Charlotte is not worried.
Jack realizes that Charlotte and Daniel have left the beach. He and Juliet go after them. Juliet is visited by Harper, her therapist on the other side of the island. Harper says that the people they are looking for went to the Tempest and Juliet needs to kill them.
Juliet and Jack head for the Tempest, but when Jack is distracted with Kate, Juliet slips away. She goes to the Tempest and tries to stop Daniel and Charlotte. Daniel is able to contain the gas and Juliet realizes that they are on her side.
Juliet and Jack have a private conversation where Juliet says that when Ben wins the war, Jack can't be around her because Ben thinks Juliet is his. Jack says Ben knows where to find him and they kiss.
Juliet finds Sun going through her things and when she asks what Sun is doing, Sun says she's looking for prenatal vitamins. Juliet wants to know why she needs more and asks where she's going. Sun says she's going to Locke's camp and Juliet says she can't do that.
When Sun and Jin are leaving for Locke's camp, Juliet tells Jin that Sun is in danger, but Jin is going to go anyway. So, she tells him that Sun had an affair. Sun slaps her.
Later, Juliet goes to Sun and apologizes, saying she had to do anything she could to keep Sun from going to Locke's camp. She doesn't know if the boat is the answer or not, but she knows that Sun has to get off the island within three weeks or she will first be nauseated all the time, then she will have shortness of breath that won't go away, then she will slip into a coma, then she will die.
Juliet convinces Sun to stay in the hopes of getting rescued.
Juliet helps to take Ray's body out of the ocean. She also asks Daniel about the sat phone.
Juliet diagnoses Jack with appendicitis. She sends Sun to the medical station to get supplies so that she can remove his appendix.
Jack wants to talk her through the surgery, watching with a mirror that he wants Kate to hold. He doesn't want to be unconscious.
During the surgery Jack is in a lot of pain, so Juliet instructs Bernard to give him the Chloroform.
After the surgery, when she's stitching him up, Kate comes into the operating room and Juliet apologizes for yelling at her. Kate says not to worry about it. Juliet tells her that Jack kissed her, but she thought it was to prove to himself that he wasn't in love with someone else. After Kate leaves, Juliet tells Jack that she knows he's awake.
Juliet gets mad at Jack for leaving his tent, but he says he was hungry. A helicopter flies over them and something drops. Jack goes to the bag and pulls out a sat phone. He says that he thinks they are supposed to follow the helicopter.
Juliet can't believe that Jack is going to go running off in search of the helicopter after he just had his appendix out.
When it's time to pick the first six to go to the freighter, Juliet says that Sun should go because she is pregnant.
Juliet helps to get people on the Zodiac, but tells Daniel she's not going until everyone is safely off the island.
Later, she sits with a bottle of rum after the freighter blows up.