Balcom was playing a game, it was plain. But to what extent? Sometimes it seemed as though Zita was his aide and would stop at nothing to succeed. Again it was that Zita played the game alone, still fostering her secret but hopeless love for Locke. Again it seemed as if Paul were playing the game, either alone or with some one else.

Just now it was apparent that Balcom and Zita, for their own ends, whatever might be the identity of the Automaton, planned a coup for themselves.

During one of Locke's absences Zita had secured access to his laboratory, and while looking around had discovered the dictagraph hidden in the desk drawer. Often Balcom and Zita, either together or alone, had taken advantage of the discovery.

It was at a time when both were using the mechanical eavesdropper on Locke and Eva in the library that Locke suddenly decided to return to the laboratory, without saying anything about it.

Zita's quick ear heard him down the hall.

"Quick!" she warned. "Some one is coming!"

She sprang toward the closet door, which stood ajar, and in an instant Balcom was with her. The two were concealed in the closet as the laboratory door opened and Locke entered.

Locke walked to his table of test-tubes and picked up one containing mercury. What prompted this action he did not know. Perhaps it was his fascination for the elusive metal. Perhaps it was some subconscious feeling. At any rate, he held it aloft and gazed at it in the light. As he did so a strange thing happened. Reflected in its surface on the glass, yet distorted like a convex mirror, he could see the door of the closet open just a crack and the evil faces of Balcom and Zita peer out.

He did not move nor did he in any way betray what he saw, but nonchalantly set the tube of precious metal down and pretended to seek something from the table. He turned slowly and retraced his steps to the library below, where he entered, holding his fingers to his lips in warning to Eva not to speak. He walked quickly over to a writing-desk, took a pencil, and began to write.

"Balcom and Zita are listening on the dictagraph. Pretend to quarrel with me."