hysician.

* * * * *

Footsteps were coming down the short hall from the back of the
building. Then Reuben Jeffries' voice said, "Go into the office. The
lieutenant's waiting for you there."

Cavender stubbed out his cigarette as Dexter Jones, Perrie Rochelle
and Mavis Greenfield filed into the office. Jeffries closed the door
behind them from the hall and went off.

"Sit down," Cavender said, lighting a fresh cigarette.

They selected chairs and settled down stiffly, facing him. All three
looked anxious and pale; and Perrie's face was tear-stained.

Cavender said, "I suppose you've been wondering why I had Sergeant
Jeffries tell you three to stay behind."

Perrie began, her eyes and voice rather wild, "Mr. Cavender ...
Lieutenant Cavender...."

"Either will do," Cavender said.

"Mr. Cavender, I swear you're wrong! We didn't have anything to do
with Dr. Al's ... Mr. Grady's cheating those people! At least, I
didn't. I swear it!"

"I didn't say you had anything to do with it, Perrie," Cavender
remarked. "Personally I think none of you had anything to do with it.
Not voluntarily, at any rate."

He could almost feel them go limp with relief. He waited. After a
second or two, Perrie's eyes got the wild look back. "But...."

"Yes?" Cavender asked.

Perrie glanced at Dexter Jones, at Mavis.

"But then what _did_ happen?" she asked bewilderedly, of the other two
as much as of Cavender. "Mr. Cavender, I saw something appear on that
plate! I know it did. It was a sandwich. It looked perfectly natural.
I don't think it could have possibly been something Mr. Grady did with
mirrors. And how could it have had the paper napkin Mavis had just
been thinking about wrapped around it, unless...."

"Unless it actually was a materialization of a mental image you'd
created between you?" Cavender said. "Now settle back and relax,
Perrie. There's a more reasonable explanation for what happened
tonight than that."

He waited a moment, went on. "Grady's one real interest is money and
since none of you have any to speak of, his interest in you was that
you could help him get it. Perrie and Dexter showed some genuine
talent to start with, in the line of guessing what card somebody was
thinking about and the like. It's not too unusual an ability, and in
itself it wasn't too useful to Grady.

"But he worked on your interest in the subject. All the other
students, the paying students, had to lose