For the longest time, Lost had stood outside the door of science fiction, parading on prime time television as a drama. We all knew that it was a scifi show but there were plenty of people who didn't and when season 4 came around, they were turned away. For us loyal fans, it was a time of great excitement and joy. The thought of time travel finally entered the canon of the show which brought just as many questions as it did answers, which brought along one of my favorite characters of the show.
Daniel Faraday. His quirky, twitchy, Einstein way about was different and very much welcome. Faraday brought answers and that's what we wanted. He is the smartest person on the show and soon became the driving force behind parts of season 5.
At first he believed that those stuck in the past could not change time, that things will happen the way they happened no matter what. After studying it up with Dharma for a bit, he then theorized that you could change the past, because humans are the Variables. Which brings us to number #11 on the countdown; The Variables.
Not only did this episode bring direction in the way of a story arc to the season 5 finale, but it brought ideas that could very well change the course of the show indefinitely. Plus it had the emotionality brought by the death of Faraday, though I do not think it will be permanent. The Variable was like a breath of fresh air for those of us that were looking for the main arc of the show to return that would eventually unite the characters. It had all the pacing and build that a season finale needs and the twist of Faraday's mother sending him back to the island knowing full well that she would be killing him was intense.