Joe said at a long-ago Halloween, I stopped off at my sailing 
club to attend the Halloween party. As I arrived, another 
member, Charlie,  was just showing up also. Neither of us 
realized it was a costume party until we got to the door. The 
doorkeeper informed us that no one would be admitted without a 
costume.  Charlie was turning to leave, when I asked, "What do 
you mean, we can't get in without a costume?  We ARE in 
costume. I'M CHARLIE!  HE'S JOE! We've come dressed as 
each other. I can't believe our costumes are so good that you 
were completely fooled!"