- Say, what do you think you're doin'?
- Nothing. Nothing.

5 seconds sound clip from the Criss Cross (1949) movie soundboard.

You can hear this line at 00:45:52.086 in the DVD version of the movie.

Quote context

[...]

- You people got intuition.

- Look, Mister, I'm sorry you lost at the races. I know what it's like myself, but, well, you shouldn't ought to bet if you can't afford to lose.

- I'll bet anything I like.

- Gosh, what have I said now?

- And I'll bet anytime I like.

- Say, what do you think you're doin'?

- Nothing. Nothing.

- Well, now, slow down, Mr. Thompson. This isn't like you at all.

- It's about time somebody did something about you nosy jokers.

- Please don't make a commotion.

- It's all right, Frank. I'll handle it.

[...]