Don't be long, David.

2 seconds sound clip from the Creature from the Black Lagoon (1954) movie soundboard.

You can hear this line at 00:53:38.390 in the Blu-ray version of the movie.

Quote context

[...]

- We're not finished here yet. We've got to make a study of that grotto, we've got to collect photographs, data...

- I've got all the proof I need.

- Get going, Lucas.

- Mark, we're not going anywhere until we've finished our work.

- All right, David, if it will make you feel any better.

- Oh, Doctor, would you mind staying behind and keep an eye on our prize?

- Don't be long, David.

- You better get some rest.

- Hi. I thought I'd come up and get some air.

- What do you suppose is taking them so long?

- David's very thorough.

- But shouldn't you be resting, Kay?

- I couldn't sleep.

[...]