Season 4 built and built until it reached the breaking point straddling the fence of action and sci fi. Keemy was the perfect bad guy, ruthless and cunning, and our heroes were helpless and desperate. I still to this day think that the pace and build of season 4 was the best so far. The story had movement and timing, it was what we were all waiting for.
There's No Place Like Home makes it to #7. This was the season finale for season 4 which tied right into the very last minutes of season 3's finale. It was huge in terms of answers posed by season 3 and 4. We saw how the Oceanic 6 got off the island, we saw what happened to the freighter, and we saw the island literally move.
But the best parts of the show I believe were those at the Orchid Station. First, the confrontation between Jack and Locke was wonderful. Throughout the whole course of the show these two have been going at it and all the emotion and anger built up from season 4 culminated in this one conversation. Then all that happens with Ben, Keemy, and Locke in the Orchid was all the more mysterious, harking back to the mysterious days of season 1.
This episode was a perfect blend of all that Lost can bring to the table; action, suspense, emotion, pacing, mystery, and science fiction. And Locke was shown dead at the end but in the future. What? BOOM