- What do you suppose he's up to?
- Who is he?

5 seconds sound clip from the Desk Set (1957) movie soundboard.

You can hear this line at 00:06:54 in the Blu-ray version of the movie.

Quote context

[...]

- May I help you?

- No. No, thanks.

- Interesting place here. Do you mind if I look around a little?

- Not at all. Make yourself right at home.

- Thank you. (2)

- What do you suppose he's up to?

- Who is he?

- Richard Sumner. Azae wants to see him.

- If he leaves here, we're supposed to trail him.

- Where'd you get that?

- Cathy.

[...]