Warren's white lips were moving in perfect synchronism, as he counted the seconds and ticks of the clock. Shirley, never so acute, cudgeled his mind for some devise by which he might overcame the other. It was hopeless. At last, just as he knew the inevitable second was almost completed, a faint rustling came from the other side of the iron door. Warren's face brightened with hope. With a nerve-racking rasp, the iron bar on the other side was raised: it was a torturing delay as the two waited!

The door slowly opened. After a harrowing pause a revolver muzzle slid gently through the crack, and a woman's voice murmured softly: “Drop the gun!”

It was Helene Marigold!

Warren's ashen face changed to purple hue, his hand trembled just enough to incite Shirley to a desperate chance. As the criminal drew the trigger with a spasmodic jerk, Shirley was dropping to the floor, whence he pushed himself forward with a froglike leap, as he straightened out the great muscles.

Together they rolled in a frenzied struggle.

“Run back, Helene. The clock will explode!” cried Shirley, desperately. Instead, she sprang into the bright room, espied the diabolical arrangement in the corner, and ran to pick it up. She saw the wire, and her deft fingers reached behind the clock to turn back its hands. Had she torn the wire, as a man would have done, the dreaded explosion would have ended it all.

“We're coming!”

It was the voice of Pat Cleary from the passageway. He rushed through the subterranean passage, followed by several men, with Dick Holloway excitedly in their train. After a titanic struggle, with the man baffled in this maddening moment of ruined triumph, they handcuffed him.

Shirley led Helene into the front compartment before she could observe the horror stamped upon the face of the murdered rogue.

The girl turned her glorious eyes to his, reached forth her hands, and then the eternal feminine conquered as she trembled unsteadily and sank into his arms.

“Break down the doors, Cleary. Out here, to the street. Pull off the hands of that clock—it's a lyddite bomb!” cried Shirley, excitedly.

One of the men used the table with clattering effect. The iron door of the front room gave way, and Shirley carried Helene up the ladder, to the main floor of the old garage. She seemed a sleeping lily—so pale, so fragile, so fragrant in her colorless beauty. He had never seen her so before! For an instant a great terror pierced him: she seemed not to breathe. But as he placed his face close to her mouth, her eyes opened for one divine look, then drooped again. A white hand and arm curled, with childish confidence, about his shoulder. He bore her thus to the big car from the Agency, which stood outside.

“Quick, down to the Hotel California,” he called to the chauffeur, “Pat Cleary can handle matters there.”

As they sped toward her apartment the roses took their wonted place in her cheeks. She sat up to smile in his face. Then she lowered her glance, with carmine mounting hotly to her brow. Helene said no word—nor did Shirley. She simply leaned toward him, to bury her face upon the broad shoulder, as neither heeded the possible curiosity of the driver on the seat in front.

At least, they understood completely. There was nothing else to say!

As Shirley left her at the door of the apartment, he turned into the elevator, his mind whirling with the strange imprisonment into which he had let his unwilling heart drift. The clerk stopped him at the lower floor.

“There's a call for you, sir. It's rush, the gentleman said!”

“Great Scott! What now?” he ran to the instrument, and he heard Captain Cronin's excited voice.

“Shirley. The man's escaped again! They just came into the place. He threw some sort of bottle at the front of the patrol wagon which blew it all to pieces. He got away in the mix-up—three policemen were injured!”

“I'll get him, Captain, if it's the last act of my life.”

To the surprise of the blase clerk, the well-known club man ran out of the hotel, dropping his hat in his excitement. He shouted to the driver who still waited in the agency machine.

“The sky's the limit, now, son. Race for Twenty-first Street and the East River. Let me off at the end of the dock. Then go back to get some men from the agency, as I'll have a prisoner, then, or they'll get my body!”

The machine raced down the street, regardless of the warnings of policemen. Shirley was confident that his was not the only car on such a mission. He reached the dock of Manby, where was waiting the expert engineer of the hydroplane. He had not planned in vain.

“Have you seen an auto go past here before mine?”

“Yes, sir, I was smoking me pipe, and settin' on the rail of the dock, when one shoots up toward the Twenty-third Street Ferry, with a cop on a motor-cycle chasin' it behind.”

“Then, quick, into the boat.”

They clambered down the wet ladder, and after an aggravating delay, the whirring engines of the racing craft were started. Shirley took off his coat, and lashed a long rope about his waist. He tied the other end of it securely to a thwart in the boat.

“What's your idee, Cap?” asked the engineer, as he waited the signal.

“There's a man trying to catch that white yacht out in the river. I want to get him, that's all. If I fall out of this boat, keep right on going, for I'm tied up now. Where's the boat hook?”

“Here, sir. Are you ready? Just give me your directions. All right, sir, we're off.”

Shirley grunted and the hydroplane sped out onto the river, in a big curve, as he directed. Like a white ghost on the river was the trim yacht, which even now could be seen speeding down the stream, all steam up. There were two toots on the whistle and Shirley feared that his man had boarded her. But the hydroplane, ploughing through the cold waves, whizzed toward the yacht, as he climbed out to the small flat stern. A small boat had swung close to the yacht now. A ladder had been lowered from a spar, while a man standing in the little craft missed it. The yacht was gliding past the boat, when another rope ladder was deftly swung over the stern.

The hydroplane was close up now, and Shirley saw his prey dangling at the end of the ladder, now in the water, struggling with the rungs of the ladder, and now being drawn up.

His engineer, with a skilful hand on the helm, swung in close to the yacht, as keen for the capture as his patron. They whizzed past at almost railroad speed, and Shirley, sprang toward the ladder. His arms closed about the body of Reginald Warren in a grip which he braced by a curious finger-lock he had learned in wrestling practice.

Two revolvers barked over the taffrail of the yacht, as the hydroplane raced onward, dragging Shirley and his prisoner at the end of the rope, through the water. Again the shots rang out, but they were out of range, on the dark waters so quickly, that before the police boat had set out from shore to investigate the firing from the pleasure vessel, the criminologist's struggle with his wounded antagonist was over.

Half drowned, himself, with Warren completely past consciousness, Shirley was pulled into his own boat as the engines were slowed down. They returned rapidly to the dock.

“Help me work him—that was a pretty rough yank. He's been shot in the hand already.”

They rolled Warren on a barrel, “pumped” his arms, and by the time the Cronin automobile had returned with the other detectives, Warren was restored to understanding again. Shirley forced some liquor between his teeth, to be greeted with a torrent of strange oaths.

“The jig is up, Warren,” said the criminologist. “As a chess-player in the little game, you are a wonder. But, I think I may at last call 'Checkmate.'”

“I'm not dead yet, Shirley,” hissed Warren. “I gave you your chance to keep out of this. But you wouldn't take it. I'll settle the score with you before I'm finished. There's one man in the world who knows how to get away from bars. I'm that man.”

Then his teeth snapped together with a click. He said nothing more that night, even during the operation for probing Shirley's bullet, and the painful dressing. At the station-house, and his arraignment before the magistrate at Night Court, where he saw some other familiar faces of his fellow gangsters—now rounded up on the same charges—he still maintained that feline silence.

And his eyes never left the face of Montague Shirley, as long as that calm young man was in sight!

Shirley merely presented his charge of murder—for the strangling of Shine Taylor. The names of the aged millionaires were not brought into the matter—there was no need. He had done his work well.

At Cronin's agency, late that night, there came a cablegram from the greatest detective bureau of France.

“The Montfleury case” was the most daring robbery and sale of state war secrets ever perpetrated in Paris. It had been successful, despite the capture, and conviction of the criminal, Laschlas Rozi, a Hungarian adventurer who had killed three men to carry his point. The scoundrel had escaped after murdering his prison guard, and wearing his clothes out of the gaol. A reward of 100,000 francs had been offered for his capture, by the Department of Justice.

“Monty, who gets all the credit for this little deal—that's what's bothering me?” asked Captain Cronin, as they sipped a toast of rare old port, in his rear office.

Shirley lit the ubiquitous cigarette, and tilted back in his chair.

“Captain: why ask foolish questions? This case ought to buy you five or six of those big farms you've been planning about—and leave you fifty thousand dollars with which to pay the damages for being a gentleman farmer.”

“And you, Monty? You know you never have to present a bill with me. What will you do with your pin money?”

“I'm going down on Fifth Avenue tomorrow and invest it in a solitaire ring, for a very small finger.”