The scene where Charlotte pokes her head up out of the lagoon after cutting herself free from the parachute so brought to mind the scene in "Apocalypse Now" when Capt. Willard's head emerges from the river. Both Charlotte and Willard are on two missions -- to find a nutcase in control of a renegade faction, and to find the meaning of their lives. You can imagine Charlotte thinking the thoughts of Willard as she ponders her next move, "Part of me was afraid of what I would find and what I would do when I got there. I knew the risks, or imagined I knew. But the thing I felt the most, much stronger than fear, was the desire to confront him."
We don't know if Charlotte was at the end of her sanity in her search for the meaning of her past and future, as was Willard. But we can empathize with the same combination of fear and exhilaration she may have felt. And we can imagine Ben reciting the words of Col. Kurtz as well: "But you have no right to call me a murderer. You have a right to kill me. You have a right to do that... but you have no right to judge me. It's impossible for words to describe what is necessary to those who do not know what horror means. As for the charges against me, I am unconcerned. I am beyond their timid lying morality, and so I am beyond caring." I don't know if TPTB were trying to create a purposeful image link with Charlotte's lagoon moment and "Apocalypse Now", even though Lost bloggers have made other comparisons to Conrad's book "Heart of Darkness" in the early seasons of the show. I'm just sayin'.