4x05 The Constant

If I were to watch an episode of Lost without binging or rewatching the whole series (which I'm doing now and will certainly do more and more times in the future), The Constant would be that episode. It work as an isolated work of art, it is its own thing even being a part of a whole. Yeah, there's a cliffhanger in the ending, but all 42 minutes of that episodes are used to the main and only storyline, focused on Desmond. It's an unquestionably important episode in the context of the season, but it manages to deliver a story that starts and ends here.

But The Constant's autonomy it's just one of the various reasons I love this episode. It gives us more insight about Desmond's character, and gives him more layers, making him even more relatable than before, it that is possible. The screenplay is just genius, not a scene is wasted, every moment is used to move the story forwards and develop the central characters. Exposition dialogue here is also done brilliantly and in an effective way, dramatizing every new piece of information they give us, and this also helps to increase the tension, as you're looking forward for more pieces to complete the puzzle that is the plot. The high-concept plot, making the sci-fi part of Lost really interesting, is one of the main reasons fans love this episode. Here, the "flashbacks" are diegetic to Desmond, who now experience time differently. He is unstuck on time, going back and forth on past and present, which the editing translates very well with the incredible transitions between the two periods. It's just perfectly designed from beginning to end, and making Penny the constant is just proof that the writers of Lost cares about their characters while thinking up a new story idea. I don't remember if I cried when I saw it the first time, but I cried this time, and every "I love you" said to Penny or Desmond is a punch in the gut as you are already invested in their story together, waiting for them to see each other again. It's Lost at its best: smart, interesting, full of questions and thrilling mysteries, thematically brilliant and character-driven.