"What put all this into your head?"

"Nothin'," muttered Dynamite Smith. Then, unable to stand the searching gaze of Doc's strangely potent golden eyes, the big oiler turned away.

It was obvious the man knew more than he had divulged. It was also evident that some sinister devilment was breeding among the crew.

Doc didn't like it.

"I'll bet that bird with the clicking teeth is stirring up the crew," Doc decided.

An idea hit him. He went to make sure he still had the treasure map he had taken off the back of blind Victor Vail by X ray.

The map was gone! Somebody had stolen it!

SEVERAL DAYS passed. Nothing happened. The Helldiver now sailed off a barren section of northern Greenland. Great blue icebergs cocked nasty snouts out of the sea all about them. The sub sloughed through mile after mile of thin pan ice.

Occasionally, where the pan ice had joined with fields of growlers, or small bergs, to make a solid barrier, they submerged and passed under.

The submarine was behaving beautifully. Long Tom's wonderful apparatus kept them out of danger, with the double safeguard of Monk's special chemicals, should something go amiss.

Monk, Renny, and the walruslike Captain McCluskey had resumed relations. Indeed, they got along handsomely. They had a hearty respect for each other's fighting qualities.

Doc hadn't found the man with the clicking teeth. He was mystified He couldn't imagine who had his treasure map, but he did not worry greatly about it His retentive brain held all details of the chart. He could sit down and reproduce it perfectly from memory.

The only discovery of note he had made was that Dynamite Smith, the big oiler, used narcotics almost steadily. Doc consulted Captain McCluskey about this.

"Sure, I knowed the swab was a dope head," the walrus assured him. "Rust my anchor, but it don't seem to hurt him. He's been usin' the stuff for years. Let'm alone, matey. The stuff just keeps 'im harmless."

Doc was not so sure about that. But there was nothing to be gained by starting trouble.

Long Tom radioed their position daily to Victor Vail. The violinist showed a great interest in their progress, as well as the exact course they intended to follow.

Sometimes Doc wondered about Victor Vail's avid desire to know their whereabouts to the fraction of a mile.

They were in a zone of continuous daylight now. The sun shone the full clock around. It was never night.

"Confound such a region!" Ham complained. He had just found out that for the last three days, Monk had awakened him at midnight, and made him believe it was noon the next day. Consequently, Ham had been losing a lot of sleep, and couldn't understand what was making him feel so groggy.

A strange, sinister tension was growing aboard the Helldiver.

The crew congregated in groups, whispering. They dispersed, or fell to speaking loudly of commonplaces when Captain McCluskey, Doc, or any of his five men came near.

"Rust my anchor, but I smells trouble!" Captain McCluskey confided to Doc.

Day after day, the submarine bored into the polar regions. Twice it traveled under the ice more than a score of hours. It made many shorter jaunts under the pack.

On one occasion, they would surely have been trapped under a vast field of ice more than thirty feet deep, had it not been for Monk's chemicals. Released from compartments in the skin of the underseas boat, the stuff let the craft reach the surface through a great self-made blow hole.

It was now but a matter of dozens of miles to the spot where the treasure map indicated the long-lost liner Oceanic lay.

Doc noted a perceptible increase in the sinister tension.

"We're in for a jam," he told his five men seriously. "The crew of this sub, part of them at least, know what we're after. And one of these surely must have my map."

Monk grinned with all his homely face, and popped his knuckles.

"Well, we ain't seen no signs of Keelhaul de Rosa or Ben O'Gard," he chuckled. 'That's one consolation."

"It's my opinion that Ben O'Gard's man with the clicking teeth is behind this trouble brewing with the crew," Doc replied.

"Confound it." declared Ham. "The clicking of the teeth should make the man easy to find!"

"That's what 1 thought," Doc said wryly. "But, bless me, brothers, I do believe that fellow's teeth have stopped clicking. I've gone around, straining my ears day after day, and not a click have I heard."

"Maybe it was really a dream Long Tom had about the man with the noisy teeth bending over him that night?" Johnny suggested.

"I didn't dream the black wig!" Long Tom retorted.

There was nothing to be said to that. The conclave broke up. At a scant five miles an hour, the Helldiver nosed for the dab of unmapped land where the liner Oceanic supposedly lay.

This was virtually an unexplored region where they now cruised. Possibly a polar aviator had flown over it, but even that was highly unlikely.

Doc retired, confident another twenty-four hours would bring action of some sort.

It did.

Johnny's frantic plunge into Doc's quarters awakened the big bronze man. Johnny's breath was a procession of gulps. His spectacles with the magnifying lens on the left side, were askew his nose.

"Renny! Monk!" he shouted. "They are both gone! They vanished during their watch on deck!"

IN flash parts of seconds, Doc was in the control room.

"Put about!" His powerful voice volleyed through the monotonous complaint of the Diesel engines. It penetrated to every cranny of the submarine, from the "hard-nose" bow up front — loaded with steel and concrete in case of collision with the ice — to the little tunnel through the after trim tanks, which gave access to the rudder mechanism.

The helmsman spun his wheel.

"Full speed ahead!" Doc boomed into the engine-room speaking tube.

Captain McCluskey lurched in from the officers' quarters. He was sticky-eyed from sleep.

"What's goin' on here?" he roared. "Rust my anchor, what we puttin' about for?"

"My two men, Monk and Renny, have disappeared!" Doc told him. "We're going back to hunt them!"

Captain McCluskey clambered up on deck. But he came down almost at once, his hairy shanks blue from the cold.

"No use!" he rumbled. "Stormin' up there! If them two swabs ain't aboard, they're in Davy Jones's locker."

McCluskey seized the speaking tube to the engine room, shouted into it: "Slow your engines to normal speed." Then, to the helmsman: "Hard over, me hearty. We're resumin' our course."

Cold and hard as a statue of bronze, Doc Savage was suddenly in front of McCluskey. Doc was big. The walrus was bigger. He outweighed Doc by nearly a hundred pounds.

"Countermand that order!" Doc directed.

Such a quality of compelling obedience did his remarkable voice have, that McCluskey made an involuntary gesture at compliance. Then he bristled.

"I'm skipper of this tin fish!" he bellowed. "We ain't wastin no time goin' back to look for them two swabs. Davy Jones has got 'em, I tell you!"

"Countermand that order!" Doc repeated. "We'll find Monk and Ham, or their bodies, if we have to winter in this ice pack!"

Captain McCluskey glowered. He had a lot of confidence in himself. He had whipped Monk and Renny in succession, and either one of them looked more dangerous than this strange bronze man.