The tension of this episode is whether or not Libby, who somehow is still alive after getting shot will be able to communicate with Jack about Michael being the one that shot and killer her and Ana Lucia. In the end, when she utters his name, Jack just assumes that Libby is just asking about his well being and nothing else comes of it before she passes on. Very sad ending.

Ana Lucia visits Mr. Eko in a dream that sets him on a course with John Locke to find the mystery that is ?, which turns out to be Station 5 or The Pearl, which is just another hatch in the ground. It's revealed here that The Pearl is the Observation Station, which was used to monitor those that like to push a button based on blind faith.