The Quiller Memorandum1966

Pol:
Let me put it this way. There are two opposing armies drawn up on the field but there's a heavy fog- they can't see each other. Oh, they want to, of course, very much. You are in the gap between them. You can just see us, you can just see them. Your mission is to get near enough to see them, to signal their position to us so giving us the advantage. But if, in signaling their position to us, you inadvertently signal our position to them it is they who will gain a very considerable advantage. That's where you are, Quiller. In the gap.