The vigil of The Shadow was ended now. Action beckoned. But not action in front of the house where a shapely blonde waited as murder bait. Marsland could be trusted to take care of affairs out front. The Shadow intended to station himself at the rear.

Leaving his rented apartment, The Shadow descended creaky wooden steps to the cellar. He threaded a noiseless way through musty darkness and emerged in a rear courtyard.

The blackness out here was almost as complete as in the cellar. The Shadow slipped across a fence. He was now directly behind the shabby walk-up in which the blonde awaited the arrival of Moe Shrevnitz.

From where he lurked, invisible, The Shadow could see the rear of the movie theater around the corner.

An alley ran along one side of the brick structure. Tiny red lights showed in the blackness of the alley.

They were emergency exit lights. The Shadow expected one of those doors to open soon.

"Mr. Johnson" had received Porky's tip-off. The murder game was about to start!

A MAN rounded the Amsterdam Avenue corner on foot. He walked slowly and carelessly. It was Porky Cane.

Porky spotted Cliff almost at once. He drifted into the dark hallway.

"How's it shaping up?"

"He ain't here yet. He oughta be soon." Cliff spoke confidently. There was good reason for it. Porky's arrival had been noted by another of The Shadow's agents. The signal had been pa.s.sed.

Moe Shrevnitz, parked in a sheltered spot two blocks away, knew it was time for his cab to move. He drove up with the swift dash of a professional hacker, pulled into the curb a few yards beyond where Cliff Marsland and Porky Cane were watching.

Moe sounded his horn, then got out of the cab and stared up at the windows of the apartment one flight up in the building next door.

The window opened and a blond head was thrust out.

"h.e.l.lo, Moe. Come on up!"

"O.K., Mabel."

With a big grin on his face, Shrevvy went into the building.

"A cinch," Cliff muttered. "How do you want to handle it?"

Porky Cane's eyes roved toward the corner. He frowned at sight of the traffic cop and the brightly-lighted neighborhood.

"Not too hot in case something goes wrong," he growled. "Might be tough if I had to make a getaway out the front door." His ugly underlip sucked in. "You wait here. I'll make a quick tour around the back. If there's a fire escape I can use after I make the b.u.mp - Shrevvy and his dame are as good as dead!"

"You gonna gun em?" Cliff asked.

"Don't be a dope! With a cop on the corner? I'll just take two quick cuts with a knife. Neat ones. From ear to ear!"

Porky grinned horribly. He faded to make sure the back yard offered easy escape possibilities.

But the killer remained in ignorance of two vital facts. The first was that Moe Shrevnitz was aware of the perilous spot he was in. The second fact concerned the girl whom Moe was visiting.

Mabel Schwartz wasn't as vulgar as she looked. Her p.r.o.nounced blond hair was a wig.

Mabel Schwartz was - Margo Lane!

THE SHADOW, hidden in the darkness behind the apartment building, expected a preliminary once-over by the murderous Porky Cane. The Shadow was not there to nab Porky, however. Not yet.

Porky was a hired killer. The unknown boss for whom Porky worked was of infinitely more interest to The Shadow. While The Shadow watched for a glimpse of the crafty little knife expert, he did not fail to keep a sharp eye on the alley that ran alongside the brick structure of the movie theater.

The mysterious "Mr. Johnson" was due to make a sly appearance in order to make sure that Shrevvy was efficiently murdered.

Suddenly, one of the red light bulbs in the dark theater alley was obscured. An exit door of the movie had swung slyly ajar.

The Shadow waited. No sound was audible to indicate the approach of a human being. The fence at the end of the alley shielded the creeping figure from The Shadow's sight. But presently a blob of darkness showed atop the fence. A figure dropped noiselessly to the ground.

"Mr. Johnson" was now at the rear of the apartment building where Moe was visiting his sweetie.

The dark figure of the criminal overlord melted behind the dim shape of a trash barrel. He crouched downward out of sight. The Shadow guessed that he was waiting for a conference with Porky.

A moment later, Porky sneaked into view. He came from a rear street. The Shadow could hear Porky chuckle as he looked upward.

A fire-escape platform was outside. It connected Margo's apartment with the ground. The ladder didn't quite reach to the ground, but a leap downward would be a cinch for a wise guy on the lam after a double throat slashing.

Satisfied, Porky started to retreat. The Shadow was puzzled. During all this time, the hidden "Mr.

Johnson" had not shown himself. He remained completely hidden by the trash barrel. It didn't look as if Porky's unknown boss wanted to talk to his henchman.

But a moment later, he made an unexpected appearance. Porky had no knowledge of peril until a harsh whisper snarled: "Stick 'em up!"

Porky stiffened. A gun had jutted into his back. He had no choice. His arms lifted.

Then he gasped as his head turned. He recognized his masked captor's voice.

"Gee, boss, I'm sorry!" Porky blurted. "I wasn't watchin' for you. I thought -"

"You fool, we're not playing marbles tonight! The Shadow may be around here somewhere! If he is, he could have put the finger on you as easily as I did!"

"I'm sorry, boss."

"Don't be sorry. Be smart! Keep on your toes! Now get out front and check with Marsland. Cliff can take care of trouble out front. I'll cover the rear after you make the kill. Get going!"

"O.K.," Porky muttered.

He faded.

The Shadow let him go. Nor did he make any attempt to move closer to the man behind the trash barrel.

The Shadow had as yet no chance to see the hidden face of Porky's boss. That chance would come soon. For the present, the sly "Mr. Johnson" could be accused of nothing more sinister than prowling in a back yard.

The Shadow wanted him for attempted murder!

CHAPTER VII. A STRANGE THEFT.

MEANWHILE, Porky Cane had returned to the doorway on Amsterdam Avenue where Cliff Marsland waited. He said nothing to Cliff about the humiliating encounter he had just experienced.

"Your job is to take care of that cop on the corner. Got a rod?"

Marsland allowed the muzzle of a shiny .38 to show briefly. Porky nodded. "Swell, And keep your eyes peeled!"

He walked past Moe's parked taxi to the adjoining doorway. He disappeared inside.

As soon as Porky had vanished, Cliff Marsland stepped backward into his own vestibule, tapped a warning signal on the door.

It opened from the inside. Moe Shrevnitz appeared. At his side was Margo Lane.

Both had been tipped by The Shadow that it was time to make an unseen departure. While Porky was entering their building downstairs, Moe and Margo had raced silently upward to the roof of the shabby structure. They had crossed to the adjoining house, had hurried down to the vestibule where Cliff Marsland expected them. A quick peek showed Cliff that the coast was clear. Shrevvy and Margo hurried to the parked taxicab at the curb. Margo got in the back, Shrevvy slid quickly behind the wheel.

The taxi drove away.

Their job was done.

The job of The Shadow, however, was just beginning. While Porky had been conferring with Cliff, an event was taking place which puzzled The Shadow. It was something he hadn't counted upon.

A second figure was sneaking from a rear exit of the movie theater.

This stealthy figure was not noticed by the first man. He remained where he was, his gaze lifted toward the rear window of Margo's apartment.

The second figure was also masked. He approached cleverly, circled the rear of the theater.

Taking plenty of time, making not the slightest sound, the second masked man crept toward the first one.

The Shadow was shielded by the dark overhang of a cellar entrance. Neither criminal could see him. But he could see both of them. He was still not sure whether this secret sneak meant an attack or a sly criminal conference.

An instant later, he knew it was an attack!

The second man sprang toward the dark trash barrel. As he moved, his gun made a dim glitter in the darkness.

The gun of the first man showed, too. He sprang from the concealment of the trash can. His weapon lined viciously at the middle of his silent foe.

He had no chance to fire. The surprise a.s.sault of the attacker gave him a split-second's advantage.

Before his victim could pull the trigger, the gun of the masked a.s.sailant swung against the skull of his foe.

There was an ugly thud. The man behind the trash can swayed. His knees buckled. He dropped in a limp huddle to the black pavement of the courtyard.

The Shadow watched the conqueror rise from a swift inspection of the fallen man. It was like watching twins. His mask was a duplicate of the first man's. The dark clothing he wore looked as if it might have been stripped from his victim.

He stood murderously taut, staring into the darkness. Some sixth sense must have warned him of danger, for he suddenly darted, gun in hand, for the cellar entrance where The Shadow was hidden. He found nothing. The Shadow was too old a hand at concealment to be caught that easily.

The masked man stood a moment, breathing heavily. Then a faint chuckle came from him. He figured his overcaution had played him false. He returned to the dark courtyard. An upward leap enabled him to clutch at the dangling ladder of the fire escape.

He went noiselessly up.

BACK at his cellar post, The Shadow kept secret tabs on the man. He saw that the masked prowler had taken a position on the fire-escape platform outside the rear window of Margo's apartment.

That was all The Shadow wanted to know. It was time to get into that empty apartment in a hurry; to get there before Porky.

He used his scant time well. Margo had left her key outside the threshold of the apartment door. It worked like a charm in the well-oiled lock.

Margo had left a dim light burning in the rear room. It was a living room. The light disclosed a cheap sofa, a couple of chairs, a table with a radio.

Swiftly, The Shadow did some furniture arranging. He turned the sofa so that its padded back was toward the door of the living room. Then he busied himself with two pillows.

They were soft pillows, exactly suitable to The Shadow's needs. He jammed one on the sofa, with its top showing slightly above the sofa's back. He leaned the other against it, its rounded corner slightly lower than the first pillow.

On the first pillow he placed something which he asked Moe Shrevnitz to leave behind. It was Moe's hackie's cap.

Perched on the rounded corner of a soft pillow, the cap looked ridiculous. It was something a child might have done to make believe that the pillow was the head of a man.

But the moment The Shadow turned off the light, it didn't look so silly. It looked remarkably like what The Shadow intended to suggest: the head of a man engaged in close conversation with a pretty blonde.

The Shadow made certain of his stage effect by viewing the sofa from the rear - as Porky Cane would have to when he sneaked in. In the darkness, just enough of the cap showed over the back of the sofa to suggest a masculine head in close proximity with a feminine one.

The Shadow laughed with sibilant satisfaction. Then his mirth ended abruptly.

Someone outside the darkened apartment was picking gently at the lock!

Porky was a crook who knew his business. It didn't take him long to get in. He crept noiselessly to the door of the darkened living room.

A knife was in his hand. Porky moved silently toward what he conceived to be two people so pleasantly occupied that they had neither eyes nor ears for anything else.

The Shadow, hidden by darkness, was also on the crawl.

His plan was grimly simple: to wait until Porky stabbed murderously at the faked pillows, then to put him out of action with a single blow. After that, The Shadow's hand would beckon to the masked man on the fire escape outside.

Porky's knife started to stab downward. But before it could pierce the pillow, he uttered a shrill yell of dismay. The fire-escape window had suddenly opened. The masked face of the man outside was disclosed. In his hand was an electric torch. The bright beam centered full on the face of the snarling killer.

The masked man fired.

His bullet caught Porky in the chest. The mobster was killed instantly. His body toppled grotesquely.

The jerk of the masked man's torch brought a yell from his lips. The moving light had revealed The Shadow. The Shadow leaped instantly forward. But his .45 remained silent. He had no wish to kill this strange enemy of Porky. He wanted to take the masked man alive.

But his foe was a man of quick resource. He flung the torch with all his strength the moment The Shadow's presence in the room was revealed.

The heavy flashlight struck The Shadow before he could duck. He was knocked off balance. By the time he could cover the distance to the window, the masked man was already in the rear courtyard, swinging desperately to the top of the fence.