- You are sure you have made up your mind?
- Positive.

5 seconds sound clip from the The Doctor Prescribed Death (Suspense) classic radio play.

You can hear this line at 00:10:24 in the radio play.

Quote context

[...]

- It must be a woman he has met recently. You've known him for four years.

- I don't think you are to blame. He is the one in wrong then and he should be made to suffer!

- How?

- You were going to kill yourself... Why should you? Kill him instead. He double-crossed you. He deserves it.

- Now, let me go a little deeper into the situation.

- Whenever a person has reached the conclusion...

- You are sure you have made up your mind?

- Positive.

- Now, if you're careful, you won't be caught. Whether you are or not, I am giving you this check for $1,000 made out to cash to be sent to your mother only after the man is dead.

- Write his name of this...

- There you are.

- I will know what has happened by the newspapers.

- I will withhold payment until I learn that you have gone through with it.

[...]