5. Juliet was a plant. We kind of figured she was up to something, but in the closing scenes of "One of Us," when we see her getting her marching orders from Ben, our jaws dropped. Of course, a couple of weeks after we learn she was a spy, she pulls a double-double cross and undermines Ben instead.

4. Ben shoots Locke. Absolutely shocking. We could hear the entire island gasp. Nobody really believed Locke would die, but when Ben left him in that mass grave, we truly didn't know what would happen. That he lost all hope, only to have Walt suddenly materialize to draw him back out, was doubly surprising.

3. Tie! Anthony Cooper, Locke's dad, is the "real" Sawyer. And Christian Shepherd, Jack's dad, is Claire's dad too. Fans have been speculating about these since last season. Of course, the "answers" add a whole new set of questions. Just the way we like it.

2. The "Red Sox" scene. We finally see that the island is not purgatory, part of a dream, or in an alternate universe. Add that to Ben's brief "live feed" of Juliet's nephew in the park, and the mysterious Naomi's late arrival, and we can be fairly confident that life in "the outside world" is still going on without the "lostaways."

1. The "We need to go back" scene. Or, as the show's creators called it, "the snake in the mailbox" moment. Jack's season finale flashbacks turn out to be flash-forwards, and the last two minutes of season three suddenly turn the whole "LOST" universe on its head. Our survivors are rescued, and get off the island. But we still don't know how, and we're even more intrigued by the fact that Jack comes to agree with Locke and Ben: leaving the island was a mistake.