When "the Monster" chases them, Juliet unlocks the handcuffs and activates the Others' sonar fence to repel it. She and Kate then reunite with Jack and Sayid Jarrah (Naveen Andrews) at the Barracks, and they make their way back to the castaways' beach camp. Sayid, Sawyer and the rest of the survivors are quick to express their skepticism and suspicions of Juliet but Jack declares her under his "protection". The Others activate an implant they previously placed in Claire Littleton (Emilie de Ravin), allowing Juliet to help her by offering a prepared solution thereby gaining the survivors' trust and respect. Juliet and Jack grow closer after she joins the survivors on the beach. Upon learning that Sun-Hwa Kwon (Yunjin Kim) is pregnant, she takes her to the Staff station to perform an ultrasound; Juliet confirms that Sun conceived on the Island, giving the latter two months left to live until her second trimester. That night, Juliet commits to betraying the Others and siding with the survivors, confessing everything to Jack about the Others' plans for the pregnant women in the camp. After Kate informs Jack and Juliet of Naomi Dorrit's (Marsha Thomason) arrival on the Island, the two abruptly venture off into the jungle to find Danielle Rousseau (Mira Furlan) and form a plan to resist the Others using Juliet's inside knowledge of their methods. They return to discover Sawyer and Sayid outing Juliet as a mole for the Others with intelligence provided by Locke while he was at Ben's camp. Juliet, Jack and Rousseau then let the rest of the survivors in on their plan: Juliet would falsely mark the empty tents of the pregnant women and when the Others arrive to kidnap them, a trap would be activated with the dynamite they retrieved from the Black Rock to kill the Others. When Karl Martin (Blake Bashoff) warns of the Others' early arrival at the behest of Alex Rousseau (Tania Raymonde), the survivors move up their schedule and divide into three groups: Sayid, Jin-Soo Kwon (Daniel Dae Kim) and Bernard Nadler (Sam Anderson) remain at the beach camp to spring the trap; Charlie Pace (Dominic Monaghan) and Desmond Hume (Henry Ian Cusick) follow Juliet's instructions to breach the Looking Glass station and disable its signal jammer; and Jack and Juliet lead the rest of the group to the Island's radio tower in hopes of using Naomi's satellite phone to