This is from my favorite movie, it's a conversation between Aunt Abby and Mortimer after he found (another) dead body in the house--
Abby: Who can that be?
Mortimer:Are you trying to tell me you've never seen that man before?
Abby:I certainly am. Well, this is a fine how-do-you-do.It's getting so anybody thinks he can walk in this house.
Mortimer:Now, you look here Aunt Abby.Don't try to get out of this.That's another one of your gentleman and you know it!
Abby: Mortimer, how can you say such a thing? That man's an imposter! And if he came here to be buried in our cellar he's mistaken. (my 2nd fave line in the movie)
Mortimer: Aunt Abby, how can I believe you?There are 12 men down in the cellar and you admit you poisoned them.
Abby:Yes, I did. But you don't think I'd stoop to telling a fib! (the best line ever!!!!)