I would like to explain my mission here.

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

You can hear this line at 00:25:00 in the radio play.

Quote context

[...]

- Interested? Will you excuse me one moment, please?

- Mr. Brady, you may go now. Please thank General Cutler and tell him that I know this gentleman.

- So much for that, Klaatu. Now, please sit down.

- You have faith, Professor.

- Faith and, uh... Uh, curiosity.

- Do sit down. I have several thousand questions to ask you.

- I would like to explain my mission here.

- That is my first question.

- It was my hope to discuss this officially with all the nations of the world. I was not allowed the opportunity.

- Now, we know from scientific observation that your planet has discovered a rudimentary kind of atomic energy.

- We also know that you're experimenting with rockets.

- Yes... that is true.

[...]