So Frodo goes into this pub.
Seated at a bar is a dark, hooded figure looking strangely insunstantial in the half light.
Frodo sits down next to the figure and remarks: "Um... you're a ring wraith aren't you" "Why yes" replies the creature with a voice like the rustling of a shroud. "Can I buy you a drink?" asks the hobbit. "Fine by me" replies the phantom.
The drink arrives and they sit in silence for a bit.
Then Frodo plucks up the courage to ask the question he has had on his mind since he came in....
"So" he says
"So .... what's a Nazgul like you doing in a place like this?"