1. Ben introduces Locke to Jacob.

He said ''Help me.'' We said ''Creeeeeepy.'' To be clear, this moment did indeed happen — but you had to have super slo-mo to see the shadowy figure, sitting in the chair in the spooky cabin in the woods, during the brilliant Ben-backstory episode, ''The Man Behind the Curtain.'' In this fiendishly designed, made-for-TiVo way, we were introduced to a character that promises to alter the destiny of John Locke and perhaps everyone else on The Island, too. Is he an imaginary friend made real? A supernatural entity trapped in a tropical purgatory? John Locke's future self, stuck in a timeless space? Or is Jacob just... a trick of the light? Bottom line: The debut of Jacob was a game-changer, only to be topped by... whatever happens tonight.

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