'Come. You would not have it said that The Shadow failed in his last experiment in master detection,
would you?
'You have done half the work; finish the rest. For this'—the harsh voice spoke slowly and
emphatically—'this is the last work you will ever do.'
The figure in the black cloak maintained its fixed position. It seemed to sway slightly, and the Red Envoy
moved closer. His eyes were watching from beneath the crimson mask.
He knew that The Shadow was noted for his ability to dodge away from gunfire. But the range was
short, now; there could be no escape.
'Ah!' The Red Envoy's tone was one of triumph. 'I see I have underestimated your ability. The
professor's watch is on the table. You placed it there. You have not yet opened it. Very well, I shall do
that later.
'I know where the key is, now: between the back of the watch and an inner surface! Excellent. That
enables me to do my work more quickly. A thin, flat key, within the watch.'
The Red Envoy was now gazing directly at The Shadow. He spoke again, and there was a note of finality
in his voice.
'I do not know your purpose,' he said, 'but it conflicts with mine. Therefore I intend to kill you. After I
do so, I may take the trouble to learn who you are. But I may mention that I already have a very good
idea of your identity.
'But before you die, let me inform you that I have detected the presence of your influence in many ways.
I have looked forward to this meeting with you. I have also made excellent arrangements for just such a
time.
'I expected that you would be here. My agents prepared for it. I myself have found time to accomplish
several things before you came here.
'Your accomplice, Harry Vincent, was in the way. He interfered, and I deal quickly with those who seek
to put themselves in my way.
'Beneath the cellar of this building is a room known as the submarine chamber. It is barred by a steel
door, that opens with a combination. The only man living who knows that combination is Professor
Whitburn, who lies there unconscious.
'Your friend—Harry Vincent—is in the submarine chamber. He has pleasant companionship in the
person of a young lady who was formerly one of my agents, but who came here to warn him against me.
I do not deal kindly with those who prove false to me.
'No power alive can save them; for water is pouring in upon them. They will live thirty minutes longer,
perhaps.'
THE Red Envoy stopped abruptly. He was close to The Shadow now— not more than four feet away.
The man in the black cloak had slumped; he seemed shorter than before. His upraised arms were
drooping. His fingers were slowly closing.
'They will live thirty minutes longer,' said the Red Envoy. His words became very slow and distinct. 'But
they will outlive The Shadow by just thirty min -'
The left hand of The Shadow made a movement; the thumb and third finger snapped together. There was
a flash of flame, and a sharp explosion, like a pistol shot, directly in front of the Red Envoy's eyes.
The man staggered back, and threw his left arm across his face. Like Prokop, he had been momentarily
stunned by the unexpected burst of flame.
(Note: When he recounted this portion of his chronicle, The Shadow raised his hand, snapped his fingers,
and produced the very effect that I have described.
He informed me that it was an astonishing trick, known as 'The Devil's Whisper,' produced by the
instantaneous action of two chemical compounds—one on the thumb; the other on the finger. The
Shadow stated that he had improved the experiment, so that he was able to produce a most startling
effect.
I have access to the chemical formula that will cause this amazing result; but I have refrained from
publishing it because of its danger.
An inexperienced person runs great chance of serious injury when attempting this experiment.—Maxwell
Grant.)
The crimson mask served as a partial protection against the blinding flare. The Red Envoy caught himself,
as he encountered the edge of the desk, and promptly fired two shots at the spot where The Shadow had
been.
But the man in black was no longer there. He had started toward the door as his opponent pressed the
trigger.
Wheeling, the Red Envoy discharged two more bullets in the direction of the departing Shadow. But his
eyes blinked beneath the red mask and the shots went wild.
The masked man closed the door of the study, and turned the key. Then he chuckled triumphantly. He
knew where to find The Shadow, if he wanted him; and the man in black had gone to attempt the rescue
of those who were in the submarine chamber.
It would be a futile attempt; yet it gave the Red Envoy the very opportunity he required. He had come to
find the plans; they were now within his reach.
He had foiled The Shadow, even though that remarkable man had made a miraculous escape from
certain death.
Working quickly, the Red Envoy pried open the back of the professor's watch. He found the key, and
unlocked the drawer. Reaching within, he seized a large envelope that lay there.
One minute later, the only person in the study was Professor Whitburn. The old professor still reclined in
his chair, with the semblance of death upon his features.
CHAPTER XXIX. IN THE SUBMARINE CHAMBER
THE water had risen in the submarine chamber. Arlette had dragged Harry from the floor, and had laid
him against the steps that led up to the steel door.
Harry Vincent opened his eyes, and gazed about him. His senses slowly came back; little by little he
realized the danger of the situation.
The water, already four feet deep, was still rising. It had reached the base of the high-set machine which
Professor Whitburn had designed as a torpedo tube.
Arlette was momentarily elated at Harry's recovery. Then the hopelessness of the situation impressed
itself upon her; and she broke down utterly.
She collapsed, limp and helpless, upon the stone steps. The flashlight rolled toward the rising water.
Harry caught it just in time.
Harry watched the water pour in; he tried to estimate how long it would be before the room was entirely
submerged. He had been half unconscious for several minutes. He had no way of judging the time.
A sound came from above. Harry groped toward the door. He was sure that he heard some one tapping.
He listened. Single taps came at intervals. Harry tapped in return.
