DEAR MISS MANNERS: How do you greet someone you know rather well when you encounter them in a shadowy situation where neither one of you should be, with people you shouldn’t be with? Just asking for a friend.
GENTLE READER: Please tell your friend that it is done with a half-smile, in which the lips move slightly but the cheeks do not. It means “I didn’t see you, and you didn’t see me.”
Miss Manners trusts that the two people are sneaking around to plan surprises for their spouses. Pleasant ones, that is.