Frasier: Very well. You leave me no alternative but to call in my marker.
Niles: What marker?
Frasier: Oh, I think you know.
Niles: You wouldn't.
Frasier: I would.
Niles: You can't!
Frasier: I will.
Niles: That was three years ago.
Frasier: I don't recall there being any statute of limitations. I distinctly recall that when you asked me to go out with Maris's sister, you said that you would owe me one forever.
Niles: But you only spent one evening with Brie. That hardly compares with what you're asking me to endure.
Frasier: Oh? Shall I refresh your memory? Midway through the opera her ermine muff began to tremble. As it turned out, she had used it to smuggle in her adorably incontinent Chihuahua. Just as I thought we'd reached the low point of the evening I suddenly felt a sandpaper tongue licking my earlobe. Alas, it did not belong to little Hervé! Fortunately my shriek coincided with the on-stage murder of Gondolfo.