THE SHADOW INTERVENES

PROFESSOR ROGER BISCAYNE took immediate charge. The discovery of the remote-control machine was of the greatest moment now.

The details of the killings could be worked out later. For Silas Harshaw, dead, could no longer be a menace:

His work was ended; his fiendish schemes had been disclosed, made harmless forever.

The little model, with its complex contrivances, was a perplexing subject.

Biscayne had the paper that showed the plan, but as he compared the diagrams with the metal box, he saw discrepancies.

His knowledge of Silas Harshaw’s mechanical methods might avail, however. Roger Biscayne was the only man who could solve the intricacies of the device.

After several minutes of studying the device and the plans, Biscayne pressed various knobs with no result. The machine was not hooked up; but he seemed to be hoping for some action. None occurred.

Biscayne ended his experiments for the moment. He asked to see the papers that had been found within the hole behind the radiator.

Cardona produced them.

One sheet bore a short, written reference that said, “Model.” Beneath it were these words:

Keys to arrangements are in drawer E.

“Drawer E,” said Biscayne thoughtfully. “Where is that? Ah! I recall! There are some drawers in the workshop. They are designated by letters. Will you find it, Cardona?”

“Sure,” said the detective.

He was starting for the door when Biscayne called him.

“Wait,” said the professor. “I’ll go with you. There may be something else, of importance in there. You can keep looking after I come back to continue with my experiments.”

As he reached the door, Biscayne turned thoughtfully and pointed to the model on the floor.

“That plug is evidently arranged for an electrical connection,” he remarked. “If you screw it into the outlet by the table, it will save time.”

Commissioner Weston picked up the model and carried it carefully toward the wall.

Biscayne left the room, accompanied by Cardona. The door closed behind them.

Weston removed the plug of the table-lamp wire from the plug hole in the baseboard.

Fredericks was ready with the plug that extended, on the end of a short wire, from the metal model. Wilhelm was looking on.

The men did not notice what was happening behind them.

Scarcely had Biscayne and Cardona gone, before the door of Silas Harshaw’s bedroom had opened. Across the floor stalked a man clad in black — The Shadow!

As Fredericks finished screwing the plug into the baseboard, the three men watched the apparatus with interest. Nothing occurred, apparently. Then there was a click at the other side of the room.

The lights went out. The glare of a flashlight revealed the three men by the wall.

Staring into the bright illumination, they could see a hand in front — a hand that held a leveled automatic.

The light swung across the room. The startled men were afraid to move. The burning glare was upon them. The gun, threatening, seemed to force them backward.

“Move,” came a low, sinister voice. “Move back. Keep moving.”

With hands upraised, the three men backed away from the gun, forced to the door of the little bedroom. They did not know who this mysterious intruder menacing them could be. Only the hand of The Shadow was visible in that light.

The three were forced into the little room. The light clicked out; the door was drawn shut by an unseen hand. The key turned in the lock.

A soft laugh rippled through the study, where The Shadow was alone.

On came the lights of the room. Beside the door, The Shadow stood and watched the metal box that lay upon the floor beside the wall.

Deliberately, he opened the door to the outer room and stood there, waiting. There was no noise from the bedroom.

Weston and his companions were not yet bold enough to give the alarm.

The Shadow was expecting something. The innocent-looking object on the floor boded no evil; yet toward it, his gaze was focused.

But for his arrival and subsequent action, three other men would be watching here now — watching idly while they waited the return of Biscayne and Cardona.

The box clicked. Its top sprang apart. From its interior emerged a greenish shape that spread in all directions.

Swirling, sweeping, a vast cloud of deadly gas spread through the room!

The Shadow had expected this. He slipped into the outer room, closing the door behind him.

The spreading gas seemed to batter at the barrier, like a ghoulish, living creature thwarted of its prey.

No living person could have survived that killing vapor.

Three men had been doomed by this, the last of the insidious traps that had been made for murder.

They had been saved, by the intervention of The Shadow!

The window by the grating was open. The fumes thinned; then whirled in the direction of the opening. Sucked by the cool air outside, the deadly gas was gradually drawn from the room.

A stifling odor still persisted, but the menace of death had passed.

Commissioner Weston and his companions were pounding madly at the door of the little room.

They had smelled the pungent odor that had trickled from the study into the bedroom. They had sensed the cause, and had flung wide the windows to protect themselves.

With fresh air close by in emergency, they were trying to break down the barrier that restrained them.

No one heeded their cries.

Detective Cardona and Professor Biscayne were in the most distant part of the apartment. With two thick doors between, the shouts could not be heard.

They were not even audible to The Shadow, who stood in the outer room. He, too, was far away.

He was standing by the open door of the laboratory. Peering from the gloom, his keen eyes were studying the men who were searching there.

The eyes of The Shadow gleamed.

For the brain behind them knew!