"The Ruby-Throated Espionage Bird Flies at Midnight."

“These pretzels are making me thirsty.”

“Ah yes, that happened to me last Festivus.”

“John has a long mustache” was a real code phrase, one of many broadcast to the French resistance on the eve of the D-Day landings and all meaning the same thing: Invasion within 24 hours.

The Longest Day, the movie based on Cornelius Ryan’s history of D-Day, opens with several scenes of French resistance members (and German intelligence officers) listening to the BBC broadcast of “personal messages” containing the code phrases. In one scene an ordinary-looking Frenchman is eating supper when the clandestine radio announces “John has a long mustache”; he stops eating, jumps up to hug and kiss his wife and leaves the house, all the time gleefully repeating “John has a long mustache!”.

Several scenes in The Longest Day revolve around the second line of a couplet from the French poet Verlaine:

The long sobs of the violins of autumn
Wound my heat with a monotonous langour.

Secret phrases have also been used by clubs and “secret societies” to enable members to recognize each other or confirm each others’ identity. Fictional usages I can think of: The lodge members’ recognition ritual in the Sherlock Holmes novel The Valley of Fear, and the phrases used by the Howards to recognize each other in Robert Heinlein’s novels (Menthuseleh’s Children, etc).

Y’know, that just made me realize that the CIA could probably solve all its problems with covert security if they have all of their operatives wear a forehead tattoo that says, “I am NOT a spy.”

On that note, James Bond should stop telling everybody his real name when he’s on a mission. “Cover identity,” James. Look into it.

What? He’s already got the perfect cover identity! He just tells people he’s the OTHER James Bond; the famous ornithologist chap. And then enemy agents are all, “Oh, so THAT’S why we overheard him talking about birds flying at midnight and such! It all makes perfect sense now. Sorry about that, Professor Bond. By all means, carry on with your nocturnal birdwatching!”

Meanwhile, the other James Bond has no idea why ninjas keep throwing him into volcano death traps every time he travels abroad to observe the flightless kakapo bird or whatever. But rest assured, he’s getting royally pissed about it by now. Someday one Bond will finally meet the other, and then the feathers will fly!

Also parodied in Top Secret!, part of the Zucker/Zucker/Abrahams stable. (Airplane et al.)

Sign: “Name a good white basketball player.”
Countersign: “There are no good white basketball players.”

Sign: “Who do you favor in the Virginia Slims tournament?”
CS: “In women’s tennis, I always root against the heterosexual.”

Damn, that was why I opened this thread! Ah, too late.

I recall in Dickens’ A Tale of Two Cities, the revolutionaries would identify themselves to one another by all using the name of “Jacques.”

No idea whether that happened IRL.

When we were bored teenagers up for mischief, we used to call a 24-hour army recruitment hotline.

We’d say: “Is Ron there?”

They’d say: “No, this is the army recruitment hotline.”

We’d say: “Oh, well, if Ron turns up, can you give him a message? The message is ‘The Gray Wolf Runs At Midnight’.” Then hang up.

Repeat for the next few hours, using various other phrases, such as “Grandma’s Cookies Are In The Oven” and “Gorky Park Is Beautiful In The Spring Don’t You Think.”

Then at the end of the night, someone would call and say: “Hello, this is Ron. Are there any messages for me?” Then we’d fall over laughing and have to hang up.

Segue to you and your buddies peeling spuds in the mess tent.

Mary had a little lamb. Stop.
My dog has fleas. Stop.
Mairzydoats and dozeydoats and I’ll be home for Christmas.
Signed:
Your loving son,
Queen Victoria.

“I am a traveller of both time and space. The stars, they fill my dreams.”

:smiley: Y’know, we HAVE a “James Bond” Street – a short, out-of-the-way one – here in SJ, named after the ornithologist, whose most famous book was on Caribbean birds. I’m waiting for some politician/activist with nothing better to do to protest about having a street named after a fictional assasin…

Well, the sign should certainly be more commonplace, but making the countersign too common could be a problem. If the countersign is a natural response to the sign, John Q. Clueless could reasonably give you the correct response without having any idea what’s going on. I think there have been spy comedies written on this theme–some ordinary person accidentally giving a spy the correct countersign, and getting drawn into a ridiculously contrived plot. So the response, while also sounding commonplace, should be a non sequitur.

Oh, and

“The green dog barks at midnight.”
“An infant on your lap may dampen your spirits.”

:smiley:

“Why is a duck?”

“Because one of its legs is both the same.”

A few weeks ago I was at the Denver airport and killing time before my flight. I saw this guy in a suit standing near the escalators, apparently waiting for someone. Just for the hell of it, I walked by and stopped to pretend to tie my shoe and said to him “The avocado harvest begins tomorrow.”

He said “What?”, I stood up and said “We shouldn’t be seen talking” and repeated “The avocado harvest begins tomorrow”, making sure to stress each syllable in a very code-phrase-y manner.

He said “I’m sorry, I have no idea what you are talking about.”

I responded “No, I’m sorry, I confused you with someone else” and walked away.

I can only imagine what the story he tells his friends is like!