THE cab was speeding up Broadway. The bright lights of the White Way were reflected in the puddles that were forming on the street, for the downpour had increased shortly after Clyde Burke had left the Marimba Apartments.

Now, in the back of the cab, Burke felt strangely weak. It must have been the trip down on the elevator, he thought; for he had been quite alert when he had entered the cab, and had given his address to the driver.

Now he experienced a tired sensation in the back of his head. The driver had closed the windows of the cab, including the partition between the front and the back. Perhaps that accounted for this weakness.

He reached to one window and tried to open it, but the knob would not turn. He tried the other window, with no result. He reached forward to tap on the partition; then dizziness seized him, and he sank back in the seat.

He heard the motor coughing. The driver must have choked it too much, Burke decided. Then he began to think of his interview with Doctor Palermo, and his mind became a curious medley of jumbled thoughts.

The cab pulled up at a traffic light. A coupe ran alongside of it, almost jamming the fender. Burke could see the taxi driver glare at the coupe; then the light changed.

The cab swung suddenly to the right. Burke heard the screaming of brakes, and managed to look back in time to see the coupe make a sudden swerve in the center of the street. It seemed to avoid two other cars almost miraculously; then it followed in the wake of the cab.

After that, Burke became indifferent to what went on. The cab darted into a side street and sped at reckless speed. Behind it loomed the lights of the coupe.

The cab passed a light as it turned from green to red. Thirty feet behind it came the coupe, ignoring the red light. The shrill sound of a policeman’s whistle reached Burke’s ears, but he did not open his eyes.

Had he done so, he would have seen the cab driver lean out and stare down the street in back of him.

The coupe was coming on. The police whistle had failed to stop it.

Now the driver of the cab was using every trick he knew to dodge away from the car that sought to overtake him. He knew that the man in the coupe was pursuing the passenger within the cab, and he was determined to prevent the capture.

IT was a thrilling race through the city streets, zigzagging along the brightly lighted thoroughfares toward the more secluded roads of Central Park. In his efforts to get there, the cab driver virtually doubled on his tracks.

Through it all, Burke was drowsing in the back seat, totally indifferent to his surroundings — utterly oblivious of his fate. If great danger threatened him, he did not know and did not care.

At last the taxi driver gained his opportunity. He shot recklessly between an automobile and a trolley car.

The coupe, close in the rear, was stopped short by the trolley. Before the slow moving barrier was gone, the taxi had turned down a side street.

Two minutes later, it reached Central Park.

The driver was more careful now. He looked through the glass partition and grinned as he saw his passenger resting in the corner of the seat, apparently asleep.

There was no sign of the coupe. It had been lost in traffic.

The cab whirled along a less traveled road. The driver laughed softly to himself.

But as he made a sharp turn that led into another road, a sudden exclamation came from his lips.

Swinging along in the same direction was a car that looked very much like the coupe he had just eluded!

The chase began again, and now it was a chase on the straightaway, with the cab at a hopeless disadvantage.

No cars were coming in the opposite direction. The coupe gained rapidly. It shot up alongside of the taxi, and the driver of the coupe relentlessly bore to the right.

He was driving the cab to the curb. The chase seemed ended.

Then came a cry of triumph from the man at the wheel of the cab. Just as his front wheels were mounting the curb, he saw a road to the right. With a quick turn of the wheel, he took the curve, nearly overturning the cab in the effort.

He could not have succeeded had the turn been sharp; but the angle was oblique, and he made it with an effort. The coupe stopped too late to make the turn.

The driver of the cab thrust his head from the side, and laughed in new triumph as he saw the coupe halt.

Then came a sudden end to his momentary victory.

Three shots sounded from the coupe. The hands of the cab driver became nerveless. His foot sought the brake pedal, but it slipped, helpless, before any pressure was exerted.

The taxi left the road and crashed among the trees, the driver hanging from the side of the front seat.

One side of the cab was tipped. Burke, completely oblivious, slipped to that side. The motor’s rhythm ceased.

The coupe turned and came up alongside the wrecked taxicab. The driver of the pursuing car leaped to the road, and yanked at the door of the cab. It yielded to his efforts.

He seized the inert form of Clyde Burke and dragged it from the cab. Lifting the man with ease, he placed him beside the driver’s seat in the coupe.

Burke gasped, and his eyelids flickered. The man who had carried him smiled grimly. He first made sure that Burke was resting easily, with his head beside the open window. Then he went back to the taxicab, where he lifted the face of the driver, and stared at the man’s features. He seemed to recognize the face.

“Dead,” he said softly. “One less gunman in New York.”

The speaker went to the back of the cab, and turned on the interior light. He noticed something beneath the back seat. Reaching in, his hand encountered an opening.

“From the exhaust,” he murmured. “Carbon monoxide. A few minutes more—”

The chugging of a motor cycle reached his ears. Then came the raucous sound of a police horn.

The man walked away from the taxi, and crossed the road in front of the coupe. As he came into the glare of the lights, his figure was revealed — a tall form, garbed in a black cloak and broad-brimmed black hat.

The man seemed like a monstrous creature of the night, a phantom shape that had emerged from nothingness.

The motor cycle was coming closer. The sounds of the cylinders indicated that it was turning into the side road.

The coupe moved away without a sound. The driver was back at the wheel, coasting the car down the slight hill that lay ahead.

CLYDE BURKE stirred. He opened his eyes, and looked weakly at the form beside him. All the events of that exciting evening were dim in his mind; for now his thoughts were centered on that strange being with whom he was riding.

What had happened?

Burke could not recall. He remembered that he had been in a taxicab — that was all. Now he was controlled by some unknown individual, who seemed nothing more than a silent monster of the night.

The coupe swung down a side street. It stopped before a house. Burke suddenly recognized his surroundings. He was at the house where he lived.

Now he was being helped from the cab; up the steps of the house; up the stairs within; to his own room.

Exhausted, Burke fell upon the bed.

He caught one good glimpse of the man who had brought him upstairs. The figure was plain in the lighted room — a tall, black form, its face hidden by the collar of its cloak, and the turned-down brim of the black hat.

The echoes of a soft, uncanny laugh came to Burke’s ears. Although he had not recognized the man, he recollected the laugh.

Burke had shut his eyes momentarily. He opened them now. The light had been extinguished. The man was gone.

The noise of a car driving away was the last sound that Clyde Burke heard that night. He fell asleep immediately, through sheer exhaustion.

IN the morning, the newspaperman recalled vividly his experiences with Doctor Palermo. He knew that his visit had been real, even though everything now seemed fantastic.

Of the events following his departure from the Marimba Apartments, Burke remembered only the beginning of the ride in the taxicab, and the concluding events of his journey, when the unknown man of the night had brought him to his room.

The morning newspaper told of a killing in Central Park. A taxi driver had been shot on a side road. The dead man had been identified as a notorious gunman. The reports mentioned the fact that the windows of the cab were jammed shut, and that there was difficulty in opening them.

But the police had not noticed the opening that lay beneath the back seat, from which the deadly carbon monoxide from the exhaust had entered the back of the cab.

Clyde Burke wondered about the newspaper report. He fancied that the wrecked cab might have been the one in which he had ridden. He seemed to remember windows that refused to open.

Still, there was no mention of a passenger in the cab; nor did the newspapers tell of a phantom man in a coupe.

Could it have been George Clarendon?

Burke recalled the soft laugh. Yet there was nothing else that might have revealed his rescuer’s identity.

“He seemed like a shadow!” murmured Burke. “Like a shadow, that came and went in the blackness of the night!”