He can't see us, he can't hear us, but one word spoken outside the barrier and he will be down on us. Do you understand that, Johnny?
10 seconds sound clip from the Robot Monster (1953) movie soundboard.
You can hear this line at 00:18:05.417 in the Blu-ray version of the movie.
Quote context
[...]
- Martha, it's all right! He's here!
- Anger won't keep the boy from doing it again. We must tell him why.
- Saw who?
- Ro-Man. He's in the cave at the end of the ravine.
- Not yet, or we'd all be dead by now. Are you sure?
- I was in the cave, painting his picture the way we saw him on the viewer screen.
- Why were you doing that, Johnny?
- So in case he did wipe out the human race, there'd be some record of how it happened.
[...]