Resting in his easy-chair, Doctor Heinrich Zerndorff sat waiting. He was lost in deep thought, his hands in the pockets of his dressing gown, his head bowed in contemplation.
It was less than an hour since Otto had left for police headquarters to bring back Clifford Gage. The trip was not a long one. Doctor Zerndorff was expecting news.
The door opened behind the seated man — so silently that Doctor Zerndorff did not hear it. There was a faint rustling. This did not reach his ears.
The first inkling that someone had entered the room came to Doctor Zerndorff when he glanced upward because of a sudden impulse. He found himself staring into the muzzle of an automatic. It was held by a mysterious stranger, a man who wore a black cloak and whose face was obscured by the turned-down brim of a broad felt hat.
"The Shadow!" Doctor Zerndorff raised his hands instinctively as he exclaimed the name.
"The Shadow!" came a whispered echo from the man in the black cloak. "The Shadow, come to claim a reckoning!"
A thin smile played over Doctor Zerndorff's features. He stared at the man before him, as though he could penetrate the disguise that covered that unknown countenance.
"A reckoning?" questioned Zerndorff.
"Yes!" declared The Shadow. "I have found The Black Master! Your deception was a great one, Zerndorff. Tonight I stood within ten feet of death and failure. But, all along, I understood. Now it is you who will meet destruction!"
The German seemed unperturbed.
"Those bombs that you pretended to be a mystery," continued The Shadow. "The key to them lay in the black disks — the tokens of the Master.
"The sensitive mechanism of the bombs responded only to the presence of a metal which contained a mild radium activity. Its glow was concealed by its black surface.
"Each token — and all your followers carried one — set off a bomb when the victim came close to it."
"I should have known it when Perry Warfield entered the office in the Financial Building. But I did not understand it until now.
"The clue to your identity was Killer Bryan. He alone, of all your men, died by a hand that did not seem to be The Master's. There was method in it.
"You wanted Killer Bryan to die with his lips sealed. You notified him — as The Master — to be ready.
You planned that he should kill Cardona, the only detective in New York who might have fathomed your schemes. You were there to slay Bryan in defense of Cardona — a justifiable homicide.
"But for my presence, Cardona would have died before you fired. Had Bryan not confessed, Henry Arnaud would have been hunted as a murderer — another dangerous foe to be destroyed."
Doctor Zerndorff let his hand rest upon the arm of his chair. The Shadow permitted the action. He knew that Zerndorff had not been prepared for this visitation; that the man who played the part of The Black Master believed his enemy to be dead.
"I suspected you when I visited you as Clifford Gage," The Shadow continued. "Once you forgot yourself — you slipped momentarily from your dialect.
"Why do you think I pretended to be working with you? Because I knew that if I treated you as a confidant, you would believe me ignorant.
"I told you that I would go into any trap that The Black Master might lay. So you furnished me with clues and prepared the trap.
"You thought I was duped; even when you knew that I had called in Cardona's aid, you did not realize that I had learned your game.
"I understand those threatening letters that you sent to yourself. They were clear to me before I reached headquarters. Otto knew too much about you — or, may I say, you feared that he might know too much?
"By planting a black token upon him, you intended to destroy him in your own car — proof that threats were directed against you. Then I came along — with the disk in my possession — and you seized the opportunity.
"I had not anticipated Cardona's failure to be at hand. I know now that you talked with him and learned enough to prepare for my coming, and direct him elsewhere.
"You had your opportunity to destroy me. You did not use it. I escaped from your impenetrable prison.
"I am here now, with one purpose — to save those innocent men. Because of the death that threatens them, I offer you life. But it must be life free from crime. One false step on your part, and our truce will be ended!"
Doctor Zerndorff bowed submissively.
The Shadow drew a paper from his pocket. He extended it to Doctor Zerndorff. It contained a brief confession of the criminologist's crime and an admission of his identity.
"Sign," said The Shadow.
Doctor Zerndorff obeyed.
"This," declared The Shadow, "will bring the governor's stay of execution. He is here in New York City tonight. He will be reached.
"As for you, Doctor Zerndorff, I can abide by my promise. I am prepared for any emergency — as I was prepared when I was in the vault where you placed me.
"Your escape is guaranteed. Tonight a fast plane will take you—"
Doctor Zerndorff raised a hand in interruption. The Shadow paused, intuitively knowing that the man had something important to say.
"I have obeyed your commands" — it was the monotonous voice of The Black Master, coming from Zerndorff's lips — "and you have promised me life. But I shall not live! I shall die!
"My career of crime will not end! It will continue after I have gone!
"Listen carefully to what I have to say. You will be interested — and powerless.
"I have three types of bombs. Vervick was the man who supplied the additional knowledge that I needed. His weakness was money.
"I acted quickly when the Evening Classic offered its reward. I phoned Vervick, telling him I was a reporter who wished to see him. I tipped off the reporter, without his knowing who had called. The understanding was silence, until Vervick reached Raynor's office.
"Meanwhile, Michaels placed the bomb. He was one of three ignorant men who served me. All are dead, as they deserve to be.
"One thing Vervick did not know. He carried the token of The Black Master. He did not know that it contained the metallic element that discharged the bombs.
"That was my invention; Vervick simply followed my instructions. He also made the time bombs and the radio bombs — the other two types. Those are the ones that I am using now!"
The emphasis on the last words had an effect upon The Shadow. He knew that Zerndorff's schemes were not yet ended. He waited patiently, hoping for further information. He was not to be disappointed.
"I have told you this to please myself," declared Zerndorff. "You are the only man who can appreciate my cleverness.
"At this moment, three giant bombs are placed. One is under the base of the Manhattan Bridge. The second is buried in the depths of the vehicular tunnel that leads to New Jersey. The third is in the largest hospital in New York City.
"How I have placed them there is a mere matter of detail. I have done it myself, within the past week, and it has been a labor of delight. Tonight, those bombs will explode simultaneously!
"You ask me when? It is now nearly eleven o'clock. They will go off at midnight. How? Ah, that is the clever part!
"Each bomb is fitted with a sensitive radio receiver. From a certain large broadcasting station, a gong is struck at the hour of midnight.
"You do not know which station? That is because the practice was started just one week ago. It is a weekly program that will be on tonight.
"My bombs are set to catch the note of that gong. Then they will explode!"
Zerndorff smiled and leaned back in his chair. The Shadow's automatic still threatened him. He knew that death was imminent.
But the man in the black cloak hesitated, hoping for one more statement from the man in whose hands lay the lives of hundreds of innocent victims.
"You are thinking of those who will die," remarked Zerndorff, The Black Master. "You think that you can save them. But wait! I have not told you of another bomb which I have set!
"This one is a time machine. It will explode at eleven o'clock, and while its victims will be few" — he chuckled — "very few, it will seal the fate of many, for it will render the midnight explosions inevitable!
"I have struck for vengeance! I brought death to Hubert Banks. I wanted death for Sforza and Pecherkin, for they were old enemies of mine. Like Banks, they shall die — despite that confession which you hold.
"For I have intended the explosion at eleven o'clock to prove that Heinrich Zerndorff was not concerned in these crimes — to make him seem to be an intended victim.
"I was to leave here at ten minutes of eleven. I have changed my plan. It is now one quarter-minute before the hour. I see the clock on the wall behind you, Shadow.
"The bomb is in this room! It will blow me to eternity — and you will die with me! You cannot escape — there are but five seconds left!"
For one short instant, The Shadow did not move. In that moment, his brain responded.
He was well within the room. The doorway was twenty feet away. The door was closed and The Shadow had locked it! In his path sat The Black Master, ready to spring for a death struggle despite the leveled automatic — ready to spring at any instant when the slightest delay meant death!
Beyond the door was the path to safety, but it was too far away!
While Zerndorff's gloating eyes still watched him, The Shadow turned. Behind him was a vaulted doorway that stood before a closetlike alcove.
Into that space The Shadow sprang, and as he huddled his body toward the floor, he turned his back on the room of doom. A terrific explosion followed.
The bomb had been placed beneath the flooring, where Zerndorff was sitting. The walls of the building were shattered by a tremendous blast.
Down into empty space fell the entire room, a shattered mass of debris — and with it fell the dead form of The Black Master!
Police gongs clanged. Patrols and fire trucks were rushing to the mass of wreckage. All that remained of Zerndorff's apartment was a huge pile of shattered masonry and woodwork.
Firemen were tugging at beams and burrowing through piles of loose stones in an attempt to rescue any who might be buried alive. For twenty minutes their frenzied labors were in vain. Then they came upon the top portion of a wooden archway.
As they dislodged a few loose bricks, a voice spoke weakly from beneath the wooden frame. With skillful efforts, the firemen cleared a space. The form of a man came into view.
He was lying on his side, his hands pressed against the framework with which he had fallen. The arch had turned aside the avalanche of debris that had poured from above.
The man's body was covered with a black cloak; a huge hat was forced down over his eyes. Strong arms gripped him and pulled him carefully through the narrow opening. Two firemen caught him beneath the arms and half carried him to a waiting ambulance.
The vehicle was clanging down the street as soon as he was placed aboard.
It stopped within a block, its path obstructed by a fire truck. The instant it halted, the man in black flung aside the interns who were starting to examine him for injuries.
Free of their grasp, he leaped to the street and staggered off through the crowd. The ambulance began to move before the startled interns could pursue their charge. They caught one last fleeting glimpse of him; then he was swallowed amid the gathered throngs.