IT was a simple matter of trial and error, playing for some lucky discovery, and praying that it would come. A complete reversal of The Shadow's usual deductive methods, but in this instance something of a hunch. There was no reason why the call should have been made from the water front, except as a matter of convenience.

Doubtlessly, the unknown man would not use that same telephone again, after learning that Methron had been murdered. But there was reason to believe that he would come from hiding, once sure that everything was safe.

Since The Shadow was the only investigator watching this part of San Francisco, the entire neighborhood appeared serene. It was the perfect setting, particularly with the fog, to coax a man out from cover.

The great clock of the ferry house tower was donging eleven when The Shadow stopped beside a dock so ancient and neglected that it had sunk almost to the water level. He had made a careful study of piers along the harbor and had disregarded this one because of its unimportance.

That very unimportance, however, gave it value as a base for The Shadow's excursions. The s.p.a.ce above the old dock was thick with fog, and that white gap made an excellent landmark. Moreover, it was the one place where The Shadow ran no risk of blundering into pa.s.sers whom he did not care to meet.

Echoing clock strokes lingered in the fog, but amid those fading clangs, The Shadow was conscious of a creaking sound not far away. After the next booming tone, he located the noise; it came from the place least expected-the very center of the old, forgotten dock.

The Shadow's own strides were noiseless as he headed out along the dock. He heard the buzz of low voices; from a dozen feet away, he sighted the glow of a feeble lantern. Becauseof the fog, the men had risked the light, never guessing that it could become a beacon for an invisible prowler.

So close that he could have stretched a hand to reach them, The Shadow saw rough, unshaven faces beside the lantern. Grimy hands came into sight; one man counted off a batch of bank notes from a large wad and pa.s.sed them to another.

"That ought to be enough, Rusty," he gruffed. "But remember what the skipper said. Don't buy all the stuff in one place. It might look suspicious."

"Leave it to me, Salvo," returned Rusty. "Only, don't get the heebies if I'm gone over an hour.

It ain't any cinch to find the right places, this late."

The men parted. As Rusty came sh.o.r.eward, The Shadow flattened, to lie unnoticed. From the dock level, he watched Salvo's lantern settle downward until it was out of sight. There was a repet.i.tion of the former creak. When it ended, The Shadow crept up to investigate.

He found a trapdoor in the dock, one so cleverly fashioned that the most intense search might have failed to discover it. Long ago, the old dock had been patched with short lengths of board, now rotten with age. Those were braced with beams beneath, and someone had sawed an irregular hole from below, cutting along the edges and ends of the boards.

Remembering a flattish ma.s.s that had followed Salvo downward, The Shadow calculated which side of the trap was hinged. He found a crack on the other edge, that would enable him to lift the level door when the time came. But that would be later, just before the ferry clock tolled twelve.

THE time came. Calculating that his own entry, if noticed, would be attributed to Rusty, the man who had gone ash.o.r.e, The Shadow dug his fingers deep between the planking. The creaky trapdoor came up, to show the light of the lantern.

For some reason, Salvo had left it hanging on a nail driven in a beam a few feet below.

The Shadow expected to see the blackness of water in the low s.p.a.ce beneath the dock.

There was water, but it lacked a deep color. Instead, a few feet below the surface lay a long ma.s.s of gray that looked like the body of some mammoth fish, stretching in both directions beyond the small circle of the lamplight.

Squarely in the center of that gray metal shape was a rounded opening that projected above the surface. It was half domed; the side that looked like a windshield was toward the outer end of the pier, leaving the open s.p.a.ce so it could conveniently be entered.

In size, appearance, the half-sunken vessel resembled but one craft that The Shadow had ever seen: the missing Z-boat called the Barracuda!

CHAPTER XI. THE CAPTURE BELOW.

CLUTCHING a curved iron bar that he found beneath the dock trapdoor, The Shadow let the trap come shut. Dangling from the bar, he lowered his feet into the c.o.c.kpit of the Z-boat.

Feeling the rung of a ladder, he lowered himself beside the half dome.

The lantern was only a few feet above him. Raising the gla.s.s, The Shadow blew out the flame. That, he imagined, was a duty expected of Rusty, when The Shadow began a downward grope into the Z-boat.

Instead of a c.o.c.kpit, he found the s.p.a.ce more like the conning tower of a submarine. Thatfitted with his own observation, the night when the Barracuda had vanished in the bay. By the time The Shadow had reached the bottom of the ladder, he heard a slithery noise above.

An inner part of the dome clamped downward, completely sealing the s.p.a.ce at the top.

Immediately afterward, slow gurgles were audible from the darkness within the Z-boat.

Someone had heard The Shadow's arrival and had mistaken him for Rusty. The ship had started to submerge.

The walls at the bottom of the ladder were rounded, like the sides of a giant cheese box.

Probing them, The Shadow could feel no opening. The darkness was clammy in its thickness; that steady gurgle, combined with the slow sinking of the floor, would have caused the average adventurer to wish he had remained on sh.o.r.e.

There was something insidious about the entire situation.

To begin with, the Barracuda was supposed to be miles out to sea, trusting to fog or ocean depths to hide her. Yet here was The Shadow aboard Prew's Z-boat, sinking in the fringe of San Francisco harbor!

The dock above was the cleverest of camouflage. The pier in Sausalito had been high enough to hide a boat that floated on the surface; this dock was not. But the Z-boat, when submerged, could be tucked almost anywhere. That was an angle the searchers had evidently overlooked.

It all indicated devilish ingenuity on the part of Felix Sergon, the master of modern piracy. It made the sudden submerging of the submarine seem like a snare, a planned event in case some challenger like The Shadow came on board.

Like anyone else in his present position, The Shadow had reason to be qualmish, but he wasn't. He still retained a well-formed theory, which, if correct, would work to his advantage.

First sight of the hidden Z-boat had shaken his theory; but added thought had told him that it could even yet be correct.

If it proved to be right, it would work out even better than he had originally hoped.

The ship had settled to the bottom by the time The Shadow at last solved the secret of the circular wall. Reaching high, he found a crevice that formed a level line all about. It meant that the entire wall was a solid cylinder that could be lowered, to give access to the interior of the Z-boat.

There was nothing in the way of a hidden switch to start the cylinder downward, but The Shadow fancied that he would not have long to wait.

The gurgles had ended. Someone had closed the submerging tanks. That done, he might already be on his way to lower the cylinder wall of the conning tower. Keeping fingers on the dividing crack, The Shadow waited.

Soon, the wall began to sink. A c.h.i.n.k of light appeared above The Shadow's head; it widened into a field of glow from a pa.s.sage leading forward. Then the light reached the ladder by which The Shadow had descended, throwing full illumination into the rounded center.

Yet there wasn't a sign of The Shadow as the wall descended. He was crouching with it, keeping out of sight beneath its shelter. When the wall reached the floor, he would be seen, but he was depending upon the chance that the barrier would stop before it went that far. THE stop came. A man was peering from the pa.s.sage, staring across the edge of the big cylinder when it reached the level of his waist. The fellow was Salvo, his unshaven face looking perplexed. He was sure that Rusty had come aboard; that was why he had first closed the conning tower and submerged the ship.

Salvo's grimy hand was on a large switch by the wall. A tiny light was burning there, a signal from a wired rung of the ladder in the conning tower. Salvo started to press the switch upward, to raise the wall again; then desisted.

He figured that the signal wire had short-circuited and decided to investigate. He laid both hands upon the wall rim and stared across like a curious neighbor peering over a backyard fence. It happened that there was a neighbor on the other side-one who could do more than hide.

From his crouch, The Shadow gave his hands an upward swoop. They plucked Salvo's neck in a tight double grasp that the fellow could not shake off. All that Salvo could do was flay about, swinging with both arms. Close to the inward curve of the half-lowered wall, The Shadow pulled away from every blow.

Salvo's struggle merely hastened the finish. Stretching too far in his desperate effort to fight free, he came half across the wall. Off balance, his weight no longer anch.o.r.ed him.

The Shadow gave a downward yank that teetered Salvo on the level. With a backward haul, he whipped the man into the cylinder, letting him hit the floor with an emphatic jolt.

Gloved fingers relaxed, but Salvo did not recuperate to renew the fight. Half choked, the wind knocked out of him, he could only groan and reach his hands feebly toward his aching throat. Meanwhile, The Shadow vaulted the curved wall and reached the switch.

Upward pressure started the wall rising. It was Salvo's turn to occupy the cheese box, which had become a perfect prison. All his storming, when he recovered, would bring no aid, for he was trapped in a place that was almost soundproof.

The Shadow went forward, seeking others of the crew. He came upon one man standing at the door of a small bunk room. Things happened there, as they had with Salvo. The Shadow smashed forward like a battering-ram, bowling the man back into his quarters. That crew member hardly knew what had struck him, except that it was something black and very powerful.

When The Shadow closed the door of the bunk room, his second prisoner was lying bound and gagged in a narrow berth.

Farther forward, The Shadow reached a tiny cabin that looked like an officer's quarters.

Beyond it was a private stairway, a narrow, circular device that led somewhere below.

The Shadow descended the spiral stairs, doubled back along a pa.s.sage. He believed that he would find the main control room farther aft, and he considered it to be his ultimate goal.

He came to a rounded bulkhead where the pa.s.sage divided. It was the s.p.a.ce into which the cylindrical lining of the conning tower could be lowered, and it also served another purpose.

It contained a central submerging tank, which explained why The Shadow had so clearly heard the sound of entering water. Those gurglings had come almost below his feet.

The question of which pa.s.sage to take seemed optional, until The Shadow caught the sound of footfalls from the other side. He waited in the dimness, until he made sure that they were approaching by the pa.s.sage on his right. Going to the left, The Shadow reached the other side of the tanklike bulkhead. He came into a brighter pa.s.sage; at the end of it was the door to the control room, standing ajar.

Ready for a glide along the pa.s.sage, The Shadow made a sudden turn. Two men had pa.s.sed around that center tank, but one of them was coming back. He had returned so suddenly that there was no time for The Shadow to pick a hiding spot.

The fellow was a swarthy crew member; his voice raised an immediate shout. The Shadow was pulling an automatic from beneath his cloak, but he did not aim it. Instead, he took a backhand cut while the other was hauling a revolver from his hip.

The swarthy man couldn't ward off the blow one-handed. The Shadow's tight fist met him cleanly on the side of the jaw.

SWIFT though his swing was, The Shadow pulled the backhand punch as it landed.

Weighted with the automatic, it did not need all the power. It dropped the swarthy man, but did not break his jaw. The clatter that the man made brought a running response from his pal who had gone forward.

The Shadow did not wait for the other to arrive. He sprang for the control room, slashed its door inward, spilling a man who was trying to close it. Slamming the door, The Shadow shoved home a bolt and swung about to aim his .45 for the man that he had floored.

He was clear across the control room, that final antagonist, huddled where he had landed against a small shelf that looked like a desk. He was moving one hand as if to steady himself; but that proved a ruse. When he swung suddenly about, the man flourished a .38 revolver that he had s.n.a.t.c.hed from a drawer.

The Shadow was face to face with a man whom he instantly recognized from a portrait that he had seen. But it was not the picture that Claudette Marchand had shown him in the boathouse. The Shadow would have recognized the flattish, wide-jawed face of Felix Sergon from having seen it in life.

This face was different. It was long and tapering, with the expression of a dreamer, except for the fierce eyes that flashed complete defiance. Those were eyes that seemed to snap commands. They had a determination that almost matched The Shadow's hawklike gaze.

Gray hair topped the man's high forehead, adding dignity to his appearance, although he had cast aside all thoughts of everything except challenge to the black-cloaked intruder who had so suddenly appeared in his preserves.

Not only The Shadow, but anyone in San Francisco would have recognized those features, for they had been depicted on the front page of every newspaper within the past two days.

The occupant of the Z-boat's control room was Commander Rodney Prew!

HE and The Shadow were face to face, gun to gun. So quickly had the climax come, that it stood a stalemate. One might fire before the other, but no shot could stay an opponent's trigger finger. If one died, both would die. The Shadow knew it; so did Rodney Prew.

Men were hammering at the bolted door, proving that all escape was blocked. That merely brought a forward thrust of The Shadow's gun, a low-pitched laugh from lips that Prew could not see. The Shadow had accepted the stalemate: death for one, death for both.

He was moving forward, lessening the range. Those gun muzzles came side by side, each pointed toward a heart. Neither adversary cared about the banging on the door; but Prewwas conscious of The Shadow's laugh. He heard a sibilant whisper almost in his ear, delivering terms that were unconditional. The Shadow was calling upon Prew to surrender.

The gray-haired commander balked. If there was a quiver to his gun hand, it was only because his trigger finger had begun to tighten. Then The Shadow's free hand was upon the revolver that Prew held, clamping it with a viselike grasp.

"You have yet to answer for murder," spoke The Shadow. "There are ways by which you may explain the past, but not the present. Remember: you are wanted by the law. My presence here is justified!"

Prew's hand went limp. The Shadow picked the revolver from his grasp, used it to gesture toward the door, as he commanded: "Quiet them!"

Prew went mechanically to the door, answered the hammering with a sharp rap. The men outside heard his voice giving crisp orders for them to return to their quarters. There were mutters, as they hesitated. When Prew repeated his words, they went away.

Head bowed, Prew returned to the desk, sank to a chair beside it. He seemed in a quandary, regretful that he had accepted defeat, yet sadly resigned to whatever fate might come. He was wondering, too, now that it was over, why he had submitted to the dynamic influence of The Shadow.

In the center of a veritable underwater fortress, The Shadow, his exit blocked, had not become a prisoner. Instead, he had effected the capture of the man who controlled the Z-boat as his hidden domain!

Realization of all that struck home to Rodney Prew. With a lift of his head, the former naval officer said wearily: "It is ended. You can take me away. I shall face whatever consequences -"

A strange laugh intervened. It carried no tone of triumph, no chill of further challenge. It held encouragement, that mirth that The Shadow uttered, for it seemed to betoken knowledge of long-hidden facts.

Amazement flickered over Prew's haggard features. A light came to his tired eyes. Next, eagerness seized him, inspired by his interpretation of the sibilant tone he heard.

Hope had replaced dejection. In The Shadow, Commander Rodney Prew realized that he had found a friend who would believe facts that no one else would credit!

CHAPTER XII. PREW MAKES PLANS.

ANOTHER half hour found Commander Prew still seated at his desk, but he no longer faced the cloaked stranger who had captured him. Instead, he was studying the calm features of Lamont Cranston, a well-dressed gentleman listening quietly to everything that Prew told him.

"I still cannot realize it," declared the commander, after a momentary pause.

"Circ.u.mstances were all against me; your finding of this ship was final evidence -"

"Not quite," interposed The Shadow. "You must remember that I saw the Barracuda that night when Sergon stole her -" "But this ship, the Lamprey, is almost identical -"

"Except that she is not completely fitted for an undersea journey; nor is she manned by a full crew. In addition, Commander Prew, the one place where I knew you could not be found would be aboard the Barracuda.

"I was confident that this was a different Z-boat, the moment that I dropped from the dock.

This ship's conning tower is much narrower than that of the Barracuda. I have a very definite recollection of how Felix Sergon bobbed about when he fired his farewell shots."

Commander Prew smiled. The Shadow had mentioned a very definite distinction between the Lamprey and the Barracuda. Prew realized that the matter of the conning towers should have occurred to him, since he had designed them.

"I constructed the Lamprey from my own funds," reviewed Prew, "but I ran out of resources.

That was when I interested Carl Methron in the work. Since I had made important changes in the design, I started my new ship, the Barracuda.

"I had stored the Lamprey here. I never mentioned her to Methron, for he might have wanted me to complete her, instead of going ahead with the Barracuda. But I preferred to produce a better vessel, a ship that would truly be a speed submersible.