- It's kryptonite, a meteorite fragment of the planet from which Superman came. It evidently gives off a ray that renders him powerless.
- We've seen it work. It really knocks him out.
10 seconds sound clip from Superman (1948) - Into The Electric Furnace (Chapter 7).
You can hear this line at 00:04:10.901 in the Blu-ray version of the episode.
