- Upstairs, nightmare boy.
- It wasn't a nightmare.

6 seconds sound clip from the The Day the Earth Stood Still (1954) classic radio play.

You can hear this line at 00:33:11 in the radio play.

Quote context

[...]

- Oh, Mr. Carpenter's got lots of 'em. He gave a couple of 'em to me. Here.

- He gave you these?

- Well, not exactly. I gave him two dollars.

- I don't know, but this whole thing... It just doesn't make sense.

- Look, Helen, do you think it's all right for you to stay here?

- There's a strong lock on my door. And Bobby's going to sleep in my room tonight.

- Okay.

- Upstairs, nightmare boy.

- It wasn't a nightmare.

- Bobby? Bobby, your shoes are soaking wet!

- Yeah... grass on the mall was kind of wet. Good night, all!

- Oh, Tom! I wonder...

- Klaatu had promised what Professor Barnhardt termed 'a little demonstration'... promised it for the following day at noon.

- It is now two minutes to twelve.

[...]