They've checked every possible channel. The Air Ministry are positive that no papers are missing that would be of any possible use to spies.

8 seconds sound clip from the The 39 Steps (1937) classic radio play.

You can hear this line at 00:47:12 in the radio play.

Quote context

[...]

- Bring me a bottle of ale, will you?

- Very good, sir.

- Oh, make that two please.

- Yes, miss.

- Pamela! Sit down.

- Did you think I was never coming?

- Not exactly, but I was getting nervous waiting.

- Well, what happened? Did you go to Scotland Yard?

- Yes.

- Well?

- Prepare yourself for a shock.

- They've checked every possible channel. The Air Ministry are positive that no papers are missing that would be of any possible use to spies.

- But that's incredible. Are you sure?

- Well, that's exactly what they said.

- I don't know what to make of it.

- I think you've been tricked.

- Well, it certainly is all very bewildering.

- Oh, I'm sorry, really I am. Look, I think you better go now.

- Ah... Go where?

- Oh, any place. Leave the country.

[...]