1 Vader: My master, the men are overworked on the construction of the Death Star. They're cutting corners.
1 Emperor: How so?
2 Vader: If you'll just follow me across your private chamber, I shall demonstrate.
3 Emperor: Very well, Lord Vader, but this had better be worth it.
3 Vader: It is, my master.
4 Vader: {peering over the edge of a pit} See? There's a whopping great hole in your floor, leading down a shaft right into the central reactor core! You could fall in and hurt yourself.

2012-05-23 Rerun commentary: And they didn't even install a railing!

The shot in the last panel was achieved by lying the set down sideways on the desk and clipping Vader and the Emperor sideways onto the LEGO studs at the "top" of the wall. I think it turned out rather effective.