RE: Paul trying to speak in code about the intruder....
The Get Smart show had that a lot.
Good ones:
Sign: The migrating birds fly low over the sea.
CS: Shadeless windows admit no light.
Sign: The wingless dove protects its nest.
CS: The toothless tiger rules the restless jungle
http://www.wouldyoubelieve.com/password.html
Good one, darn funny.