There was a barbed-wire gate at one side of the enclosure for coal and supply trucks to enter. There was another smaller gate secured by a heavy lock where Roemer and those who came to see him had been in the habit of going in and out.
The Agent paused beside this. A policeman patrolling his night beat sounded measured footsteps up the block. The Agent waited in the light of a street lamp till the cop came alongside.
The policeman stared at the Agent, gave a sudden start, then touched his cap respectfully.
“Good evening, inspector,” he said. “Can I be of any help, sir?”
Agent “X’s” daring disguise had proven adequate. He shook his head, and, when the cop had gone on, he took the kit of chromium tools from his pocket. There were many of them, seemingly fragile, yet cunningly shaped. He held one in his hand, a glittering piece of goosenecked steel. With quiet efficiency he attacked the lock on the gate. In less than a minute the lock snapped open and Agent “X” passed inside.
He moved like a shadow across the barbed wire enclosure toward the jumbled buildings that loomed ahead. He drew another tool from his pocket kit, approached the door of the largest of the buildings. His hand moved toward the lock, then paused. He was staring at the door’s edge.
Someone had been at work here recently. He squinted, nodded understandingly. A burglar alarm had been installed since the murder had taken place. This building was Government property. The work of Mark Roemer had been subsidized by the Government. The Government had taken pains to checkmate any further attempt to pry into the secrets that the building held.
Agent “X” reached into his kit again, drew out a slender band of coiled metal that was like a steel measuring tape. He unwound it from its cylindrical case, probed with the end of it around the door’s edge till he found the plates of the burglar alarm.
Forcing the end of the thin steel under the inside plate, he drew the steel to its full length and thrust the other end into the moist ground.
The Agent knew the workings of burglar alarm systems — knew that there were two plates, and that it was the separation of these two plates when the door was opened that caused the alarm to sound. By grounding the inner plate he had prevented the breaking of the electric circuit.
He now opened the door quietly and entered. Once inside, he clicked on a flashlight with a bulb no larger than a kernel of wheat. It threw a tiny spot of radiance through a concentrating lens, a beam that would not be seen from outside but which enabled the Agent to pick his way. His eyes were glowing eagerly.
He located the laboratory in the building. Here were storage tanks for chemicals and jars and bottles of strange, poisonous-looking acids. Here were gleaming, copper-sheathed retorts, crystal refiners, an air-compressing machine, vacuum pumps, and a refrigeration plant. Here was all the paraphernalia for research into little-known and sinister fields of science. Here was where Mark Roemer and his assistant had worked.
It was from this laboratory that Roemer had been kidnapped. It was in it that the body of his assistant had been found. There seemed to be the dullness of death in this deserted building mingled with the acrid odor of chemicals.
Agent “X” walked to the laboratory’s window, the one that newspaper accounts of the crime said had been jimmied. For long seconds he studied it, raising it softly, examining the marks that the intruder’s jimmy had made. Then he gave a low exclamation.
Marks in the wood of the window frame showed that the pressure which had caused them had come from inside the building. They had been made after the window had been opened. Someone had left those marks purposely, made it seem that the window had been jimmied. The police had apparently overlooked this.
Like a flitting wraith, the Secret Agent moved about the big laboratory, studying, sniffing, nodding to himself. A wide field of chemical research had been under way here. It was impossible to say without careful study what angle of it Roemer had been concentrating upon before his disappearance; but the Agent had his own ideas.
FEELING that he had learned all he could, he left; reconnecting the burglar alarm again, leaving the building as he had found it. He made his way down the street toward a brightly lighted avenue, passing the bulky form of the patroling cop placidly walking his beat.
The Agent’s next stopping point was a vacant lot a half-mile farther on. It was a dreary spot, filled with rubbish and the rusty bodies of old motor cars. A lean cat whisked from behind a barrel looking back at him with lambent green eyes.
The Agent moved between tin cans and piles of rubbish, pausing at last to stare at a bare spot on the ground.
News photographers a few days before had taken pictures of this spot. The tabloids had published the pictures. A thrill-hungry public had gazed at them. It was a spot of death — the spot where a taxi man and a petty criminal, a lone jackal of the underworld, had been found dead. The bodies were gone now; but Agent “X,” reconstructing the crime bit by bit, seemed to see their empurpled faces and outthrust tongues at his feet. They, too, had been killed by the unseen hands of the ghostly strangler.
He looked back at the curb, at the place where the deserted taxi had been found. Then, pondering silently, tensely, he walked on and engaged another cab.
This time he went back toward the city limits.
When he reached the street where the murder of Scanlon had occurred, he ordered the driver to proceed slowly. The Federal detective’s body had been removed. The police cruiser and headquarters car were no longer standing at the curb. But, up the block in front of the address written on Scanlon’s cuff, an official car of some sort was parked.
Agent “X” told his cabman to drive on and turn a corner. He paid his fare, got out, and walked cautiously back.
The house that corresponded to the number on Scanlon’s cuff was a simple two-story affair. There was a light burning on the ground floor. A hedge ran around the yard.
The Agent walked by the chauffeur who dozed at the wheel of the parked car and slipped quietly into the yard. He moved like a shadow along the building’s side. His heart was beating faster now. He was running a great risk. Who was inside?
The shades were closely drawn. He couldn’t see. He would have to trust entirely to his disguise. But before revealing himself he wanted, if possible, to learn what was going on.
He slipped quickly to the rear of the house, tried a door. It was locked, but once again he took his tool kit from his pocket and deftly picked the lock. Then, so quietly that those inside heard nothing, he entered.
He tiptoed to the closed sitting-room door and listened for a moment. A man and a woman inside were talking. The man had the bullying voice of a routine police officer. The tones of that voice were strangely familiar.
“She must have told you,” the man was saying. “We found it on her. She must have known what it meant.”
“No — no,” the woman replied. “She didn’t tell me anything. After Cora went to work for Mr. Roemer I never saw much of her. She was secretive always. I never questioned her.”
“It’s the only clue,” the man’s voice continued stubbornly. “If you can tell me what it means, you’ll be helping the police. You’ll be helping to run down the murderer who killed your sister. Did she ever own a car?”
“No — she didn’t drive, I tell you. She never had a car.”
“You’re sure of that?”
“Yes — yes, I’m sure.”
There was silence for a moment, and in this silence Agent “X” quietly opened the door. His eyes were gleaming. His body was tense. The action he planned was high-handed, unusual even for him; but impulse had its place in his working methods. Here was an opportunity! The police had one clue — one he hadn’t heard of. What was it? The police might not like it — but, to aid in running down the murderer of Scanlon, he would demand that they share that clue with him.