This post is more than 2 years old.
Wow. After last week's somewhat slow episode, this one really ramped stuff up. It was a Locke-centric episode, which is normally good, and this proved to be no exception.
Let's cover the back story first. Locke is seen preparing to ask his girlfriend to marry him. Before he can do so, they find out that his father has passed away. Later on though his father shows up. We find out that he is hiding from some guys he stole a large sum of cash from. Locke's father asks him to bring the money to him, but when he does, Locke's girlfriend catches him and leaves him for good.
So - what's going on in the present time? Locke is sitting around in the hatch when he hears a faint noise being broadcast. It's not coming in well, but when it clears up, it's a countdown. When it hits zero, walls fall across the hatch. Locke and Henry are in the same area, so Locke enlists Henry's help to try to lift one of the walls. There is an accident, and Locke is trapped under the wall. He asks Henry to go through the ducts and enter the numbers. Time is running out and we hear some of the same noises we did last time when the number wasn't entered in time, but this time something amazing happens. A black light turns on, and we see.... something. It appears to be a very large diagram written on the wall. To be honest, I couldn't see anything clear in it. I'm sure there will be a picture on the net within the hour, and when I find it, I'll add a link to it. The diagram was very detailed and seemed to have a lot of information. But what that information was I have no idea.
Outside - Jack and Sayid run into each other at a parachute drop of fresh Dharma supplies. This really didn't surprise me. We knew that Dhara was still actively supporting the place. Although I'm curious why no one heard a plane go over.
In the meantime, Sayid and his crew discovered the balloon and grave site. But when they return, we find that Henry Gale was the one buried in the grave. Our "Henry" was definitely not telling the truth.
Interesting note: In the preview for next week, we see Sayid threatening "Henry", and he clearly says, "He will kill me!" Or something like that. If you remember a few episodes ago, the Others in the Dharma medical facility also mentioned an ominous "He". So "He" must be the guy behind it all.
As before, you can discuss the episode here, or on the LOST forums.
Edited: That didn't take long. Here is a screen cap of the diagram.