AMBRIL. "This is a curious artifact. It is called the six faces of delusion. As you can see, however, there are only five faces."
THE DOCTOR. "It's a headdress?"
THE DOCTOR. "Put it on. ...now, you, count the faces."
ASSISTANT. "One, two, three, four, five... six."
THE DOCTOR. "Exactly. The sixth face of delusion is the wearer's own. That was the whole idea, don't you think?"