I'm trying to figure out the word play behind this dialog (it is taken from A Bit of Fry and Laurie show - http://www.youtube.com/watch?v=WaqZpcPEZEY):
- Good morning.
- Right. Can I help you?
- Yes, your face, my arse.
- No, I said, "Can I help you? "
- Oh, I see. Yes, I'd like some information, please.
I've tried to google it and have found a similar slang "answer" for "Do you have a match?" question. I understand that it that case word play comes from the fact that "match" has two meanings to it.
But it seems that "Can I help you?" has only one meaning to it - where does "Yes, your face, my arse." come from?