Day 21 (Alt) - Written In Code
Of course he knows all the ciphers, all the morses and rudimentary binaries and whatever else London passes their way, but with all his past philandering, he really does have to admit that French is one language he never expected to learn during the war.
Not this kind of French, anyway. Instead of "merde" and "putain" and "cul-bite" or "liaison" and "mange-moi" and "je veux te baiser" or however you like, it's "mon pôte" and "amour sans fin" and then whole sentences', paragraphs', worth, month after month...year after year.
It's no secret. That's why they don't bother encrypting it.