Mmm. Heh! But he doesn't know it... yet.
5 seconds sound clip from the Wuthering Heights (1939)) classic radio play.
You can hear this line at 00:31:44 in the radio play.
Quote context
[...]
- I beg your pardon? So I claimed my inheritance.
- Cathy will understand. It's an old 'joke' between us.
- I see. Are you staying long in the neighbourhood?
- I'm staying the rest of my life.
- Really?
- No! You mean...? Cathy's brother Hindley sold out?
- Mmm. Heh! But he doesn't know it... yet.
- That's as underhanded a piece of work as I've ever heard of.
- If I'd known that his holdings were being stolen by a stranger...
- May I remind you that I am not a stranger? I'm merely a neighbour.
[...]