He's out of his mind.
2 seconds sound clip from the Murders in the Rue Morgue (1932) movie soundboard.
You can hear this line at 00:51:15.390 in the Blu-ray version of the movie.
Quote context
[...]
- Monsieur, the prefect will question you now.
- Now, you might as well come quietly. Don't try and make any more trouble.
- Young man, what is your name?
- Oh, I can tell you who committed the murder and where you can find him.
- Who?
- An ape.
- If you don't listen to me now, you'll be guilty of the second murder.
- Second murder? So you know there has been one?
- Yeah.
- If you'll only listen to me, I'll explain.
- Very well, tell us what you know.
[...]