It's Old Nick himself. We must be dead and we don't know it.
5 seconds sound clip from the The Snow Goose (1954) classic radio play.
You can hear this line at 00:21:30 in the radio play.
Quote context
[...]
- Blimy, look at the bullets whipping the water up all round him.
- I hope he makes it. That's where they sunk the Ramsgate motorboat this morning.
- Look out! Another of the cheetahs! Get down!
- Here. No, they didn't get him. They didn't get him. He's going to make it.
- Oh, look at him now. A black beard, humpback, and a sort of claw for his hand.
- It's Old Nick himself. We must be dead and we don't know it.
- Good man! The seven are the nearest. Get in. You four, you and you men over there.
- Yes, you fool! Don't stand there staring. Get in, quick!
- Yes, sir. Come on, Lofty. This is it.
- Come on, lads. In you get. Don't mind getting your feet wet.
[...]