"Then the thirteenth person—"
"May be the murderer!"
Weston stared reflectively. He seemed to be visualizing the scene as he had read of it, and as Cardona had described it. He looked at Cardona questioningly.
"What became of the odd person?" he asked.
"He must have left," returned Cardona. "Castelle isn't sure, but he thinks there were seven men and six women in the place. There were six men and six women — Harvey included — when the house detectives got there. That makes an odd man in the crowd."
"How could he have disappeared?"
"There's a mystery," declared Cardona. "It's pretty near as bad as the ghost theory. When he went, he must have slid out the door just after the lights came on.
"He had a straight hallway ahead of him. No doors on either side. He might have slipped along to the balcony above the lobby, then down the stairs at the side.
"Castelle grabbed a telephone, and called for help right after the lights came on. The house men were there mighty quick. But when you're dealing with an uncertain time element—"
"It would have been possible, however?" interjected Weston. "Possible for a man to have left by the hall?"