You know I wouldn't do that.
3 seconds sound clip from the The Asphalt Jungle (1950) movie soundboard.
You can hear this line at 00:13:57 in the Blu-ray version of the movie.
Quote context
[...]
- If I ever see you running over a cat, I'll kick your teeth out.
- I'd take you apart if you were about a foot taller and straightened up a little.
- Suppose you want your heater back. Well, you ain't gonna get it. What do you think of that?
- I mean it. Go on, get sore. Smack me down.
- You know I wouldn't do that.
- Look, Dix, take my advice and knock off for a while.
- The happiness boys are on a rampage. Headquarters has given them the push.
- I can't afford to knock off.
- Oh, stop worrying. I'll stake you.
[...]