He drove quickly to his apartment on Jefferson Avenue, disguised himself as Greenford again. The spy was still unconscious, breathing peacefully in the closet.
The streets were deserted when “X” reached the square. It seemed a place of ghost houses. There was only one light burning. That was across the square in the beer saloon, dimly seen through the jumble of playground equipment. The rusty chain of a swing creaked in the night wind as the Agent passed it. It made a sound like a body swinging on gallows.
With the faces of the three slain detectives and the butler still before his mind’s eye, the horror of the empty house seemed to have deepened.
There was not only the chill of mystery as he climbed the steps now. There was a living threat. The brooding, towering menace of death.
He pulled the ancient bell handle, half expecting that this time there would be no result. How could the man who called himself the Black Master be everywhere at once, unless he was the very spirit of evil itself?
Echoes clattered inside the house. A minute passed. Then again the lock of the door clicked and the old door swung open, moved by unseen hands. The Agent entered quickly. As he moved along the black hallways, he struck a match and noticed something that seemed to add to the ghostliness. His own tracks still showed in the dust. They had not been disturbed. There were no others beside them. It was as though he had entered a house peopled only with sinister spirits.
He was slightly ahead of time. He waited in the still top-floor room, waited till a clock somewhere outside boomed twelve strokes. Then suddenly there was a dry rattling in the room. For an instant it was horribly reminiscent of a snake or of some huge reptile uncoiling. Then the voice he had heard before spoke.
“The Black Master salutes you, Greenford. What is your answer? Speak loudly.”
Imitating Greenford’s foreign accent, the Secret Agent spoke. It seemed as though he were talking to the blank walls of an empty room. It was uncanny, spine-chilling. His own voice reechoed in his ears.
“My government is prepared to pay a large sum for what you have. It is prepared to pay a hundred thousand dollars.”
There was an instant of silence, then a harsh laugh broke out. There was bitterness, mockery, contempt in the laugh.
“A hundred thousand dollars! A hundred thousand! You come here and offer me a hundred thousand — for something that will affect the destiny of nations? For something that holds in it the secret of death itself?”
The Agent injected excitement into his answer.
“Give me time then. Perhaps I can make them understand — make them pay more. Perhaps I can raise it to two hundred thousand!”
Again the mocking laughter filled the room.
“Two hundred thousand! The thing that you seek to buy has already snuffed out the lives of eight people. A nation could fall before it as well.”
“Eight people!” The Agent gasped the two words, baiting the hidden voice on.
“Yes, eight people. When you read the papers tomorrow, you will understand.”
“What is your price then? What shall I tell my government? There must be some reason in this.”
“A million dollars,” the voice said. “That is my price today. If I am goaded too far, it might rise. Those who do not pay my price will regret it. Tell your government that.”
“It is too much — it is impossible,” said the Agent. “With governments bankrupt, with revenues lessening, how can you expect so much?”
“Fool!” said the voice. “I ask less than the price of one submarine, the cost of one dirigible. You have seen how I can strike. Beware.”
“Give me one more chance,” the Agent said. “I’ll see what I can do.”
“Tomorrow then — at the same time. It is your last chance. I cannot deal with fools and bankrupts. There are other countries that will pay.”
The voice ceased speaking. The room was still. The Agent asked another question; but the walls echoed his own voice back. He went into action suddenly, took a short-bladed, gleaming tool from his pocket.
He moved sidewise, ran the sharp tool down the wall, ripping at the paper. It was from there he decided that the voice had come. Was there a secret room beyond, or—
He gave a harsh exclamation. The thick paper had come free. Behind it, sunk in the wall, was the bell-shaped outline of a radio loud-speaker. There was the small circle of a microphone below it. He ripped at the plaster feverishly, saw the compact radio mechanism behind it, and uncovered antenna wires leading to the roof.
The mystery of the voice in the room was solved. But the Black Master was as much a mystery as ever. The trail of the horror killer led on — into a fog bank of terror, eeriness — and doubt.
Chapter XII
AS he left the house he stopped for an instant to examine the door in the lower hallway. The mechanism that operated it was concealed. But he found a wire attached to the old bell cord, leading upward. He pulled this wire and waited. Seconds passed and the door opened. He understood then that the radio impulse sent out from the same station as that of the voice which had addressed him was responsible for its mysterious movements. Battleships and airplanes had been operated by radio control. The Black Master had installed radio controls on a door.
With burning, intent eyes he descended the steps and moved along the street. Again he had the uncanny sense that he was being followed. He paused with a cigarette in his hand, and, before lighting it, stared back through his cupped fingers.
A dark, flitting shadow moved into an areaway behind him.
As though he had seen nothing, the Agent turned and continued his way along the street. But at the next corner he ducked out of sight into a doorway. Skilled himself in all the arts of shadowing, he planned to turn the tricks on his shadower.
Standing in the blackness of the doorway, he looked back. A small man came around the corner, moving with quick, furtive steps. The man stopped suddenly as he saw that the block ahead of him was empty.
For a moment the street light fell upon his face. His features had a vicious, pallid cast. He looked as though drugs had ravaged his body, made him a depraved and inhuman wreck. His eyes were glittering with feverish brightness, his face muscles twitching. Suddenly he retraced his steps, seeming to sense that he had been tricked.
The Secret Agent waited a moment, then came out of his hiding place. Walking close to the side of the buildings he followed the small man ahead. So deft and sure were his movements that he seemed no more than a blending shadow.
He caught sight of the small man again as he rounded the corner. From then on it was the other’s turn to try and shake off pursuit.
He seemed to think he had. Six blocks from the square, he came out into the light, walked across the street, and entered a telephone booth. The Agent, watching from the other side, could see him making a call.
Then the utterly unpredictable happened. A movie house next to the drug store disgorged its audience abruptly. The street became clogged and choked with jostling people. The hophead slipped out of the booth. His small height made it impossible for any man to see him.
The Secret Agent elbowed his way quickly through the crowd. But, when he reached the other side of it, the small man was gone.