It'll do you no good.
4 seconds sound clip from the Meet John Doe (1941) movie soundboard.
You can hear this line at 01:57:43 in the DVD version of the movie.
Quote context
[...]
- I don't know what gave us the idea that he'd attempt anything like this.
- I guess you're right. I'm afraid the joke's on us.
- Let's go. I hope nobody finds out we've been here.
- I wouldn't do that if I were you, John...
- You'll be buried in Potter's Field and you'll have accomplished nothing.
- I've already mailed a copy of this letter to Mr. Connell.
- John, why don't you forget this foolishness?
[...]
