"Wait."

He stepped to a sideboard, drank a glass of brandy, and then resuming his former seat, said in a perfectly cool tone:

"This is a very remarkable piece of acting, Mr. Alvarez. Who is this person?"

"My twin brother and my aid."

"And what does this all mean?"

"It is a test of identification."

"You are a wonderful man."

"I am?"

"Yes."

"How?"