Keep it down.
1 seconds sound clip from Superman (1948) - Into The Electric Furnace (Chapter 7).
You can hear this line at 00:11:37.023 in the Blu-ray version of the episode.
Quote context
[...]
- Well, we can't do anything, but I can go and size up the situation.
- Oh, no, no. That'd spoil everything. Nobody would show up if two of us were seen.
- Papers, eh? Read all about Superman.
- Don't turn your head. Just answer my questions.
- Very well, what do you want to know?
- Only that he'd agree to almost any terms to save Jimmy Olsen.
- Superman won't appear until you first turn Jimmy loose.
- You said he'd agree to any terms.
- How will Superman know if we'd let Jimmy go?
- Well, you're going to take me to where you're holding Jimmy. I'll see you release him.
- Remember one thing. If this is a trap you're fixing up, you're in it too.
[...]