Now, keep your eyes open. He'll be hard to see in these woods unless you're right on top of him.
6 seconds sound clip from the X Minus 1 - A Gun for Dinosaur by L. Sprague de Camp classic radio drama series.
You can hear this line at 00:17:37 in the radio play.
Quote context
[...]
- Look, on your toes, chaps. The theropod that's been at this carcass is probably nearby.
- How do you know? You see how the hide's been ripped off and the bones are scattered?
- Well, that's what we came after.
- Raja, you take Mr. James through that way and we'll parallel you forty feet distant.
- Now, keep your eyes open. He'll be hard to see in these woods unless you're right on top of him.
- We pushed through the edge of the copse, looking for the huge flesh-eater who'd been at the carcass.
- I could hear James and the Raja pushing ahead on my right.
- We were separated by a gully when I heard a noise ahead on our left.
- I don't know. Take the safety off your gun.
[...]