“Empty Room”
Sokka: These lanterns are terrible. I can’t see. Why would you want to use fireflies for light?
The Mechanist: Hey, close that up! They’ll get loose. Fireflies are a non—flammable light source.
The Mechanist: Cover your nose and hold your breath.
Sokka: Okay, so you brought me all the way down here to see an empty room.
The Mechanist: Wrong.
The Mechanist: It’s filled to the brim with natural gas. Came across it my first time here. Unfortunately, I was carrying a torch at the time. Nearly blew myself and the whole place even more sky high. Thought my eyebrows would never grow back. Anyway, there’s a vital problem that needs solving. From time to time we have gas leaks and they’re nearly impossible to find.
Sokka: So this place is an explosion waiting to happen?
The Mechanist: Yes, until I figure out how to locate something I can’t see, hear, smell or touch.