Inside the box were other lenses, spinning disks perforated with small holes, sensitive photo-electric cells — a compact television transmitter. Waterproofed electric wires led from this down into the water.

Long Island Sound was not deep at this point. The under-the-polar-ice submarine, Helldiver, rested on the bottom. The wires from the television box entered the undersea boat.

Before the scanning disk of the television receiver in the sub, six men stood. They were a remarkable group.i. Six more unusual men than these probably had never assembled. Each possessed a world-wide reputation in his chosen p profession.

There was "Renny," a hulking six feet four and two hundred and fifty pounds of him — with possibly fifty pounds of that weight concentrated in a pair of monster fists. Renny had a sober, puritanical face. About the only entertainment he permitted himself was knocking panels out of doors with his huge fists — a stunt he pulled at the most unexpected moments. As Colonel John Renwick, the engineer, Renny was known in many nations, and drew down fabulous fees when he worked.

There was "Long Tom," pale and none too healthy— looking, the weakling of the crowd in appearance. His looks were deceptive, though, as more than one big man had discovered. As Major Thomas G. Roberts, the electrical wizard, he had worked with the greatest electrical minds of his day.

"Johnny" — William Harper Littlejohn — was tall, gaunt, studious and bespectacled. He seemed half starved, with shoulders as bony as a coat hanger. Once he bad headed the Natural Science department of a famous university. His knowledge of geology and archaeology was profound. His books on these subjects were in every worthwhile library.

Two individuals stood on the edge of the group and scowled at each other like a cat and dog. They were "Monk" and "Ham." They always seemed on the point of flying at each other's throats. They swapped insults at every opportunity. Yet Ham had several times risked his life to save Monk, and Monk had done the same for Ham.

They were as unlike as men could be. Monk was a hairy monster of two hundred and sixty pounds, with arms some inches longer than his short legs, and a face incredibly homely. He was a human gorilla. The world of chemistry knew him as Lieutenant Colonel Andrew Blodgett Mayfair, one of the most learned chemists alive. But he looked dumb as an ox.

Ham was slender, lean-waisted. His clothing was sartorial perfection — tailors had been known to follow Ham down streets, just to see clothes being worn as they should be. His business cards read: "Brigadier General Theodore Marley Brooks;" and he was possibly the most astute lawyer Harvard ever turned out. Ham carried a black cane of innocent aspect — a sword cane, in reality. He was never to be found without it.

The sixth member of the group was a mighty man of bronze — Doc Savage.

MAN of mystery, the radio commentator had labeled Doc Savage. Wizard of science! Muscular marvel!

The radio speaker had not exaggerated. Doc Savage was all of these things. His mental powers and strength were almost fantastic. He was the product of intensive expert, scientific training that had started the moment he was born.

Each day of his life, he had performed a two-hour routine of unusual exercise. Doc's powers might seem unbelievable, but there was really no magic about them. Rigid adherence to his exercise, coupled with profound study, was responsible.

Doc was a big man, almost two hundred pounds — but the bulk of his great form was forgotten in the smooth symmetry of a build incredibly powerful. The bronze of his hair was a little darker than that of his features, and the hair lay down tightly as a metal skullcap.

Most striking of all were the bronze man's eyes. They glittered like pools of flake gold when little lights from the television scanning disk played on them. They seemed to exert a hypnotic influence.

The lines of Doc's features, the unusually high forehead, the mobile and muscular and not-too-full mouth, the lean cheeks, denoted a power of character seldom seen.

"There goes the last of the flyers!" Doc said.

Doc's voice, although low, held a remarkable quality of latent power. It was an intensively trained voice — everything about Doc had been trained by his exercise routine.

"They sure enough thought it was the sub they had bombed," grinned Johnny, the bony archaeologist. He adjusted the glasses he wore. These spectacles had an extremely thick left lens which was actually a powerful magnifying glass. Johnny, having practically lost the use of his left eye in the War, carried the magnifier there for handiness.

"Our contraption fooled them," Doc admitted. "But it might not have worked so well in daytime. A close look would have shown the thing was only a strip of canvas painted the color of steel, and some oil barrels, pulled along under the surface by a torpedo mechanism."

At the rear of the group, Monk stopped scowling at Ham long enough to ask: "You made that torpedo mechanism a couple of days ago — but how'd you know that early that something like this would happen?"

"I didn't know," Doc smiled faintly. "I only knew we were barging into trouble — and made preparations to meet it."

"If you was to ask me, we didn't have to barge into it," Monk grinned. "It came right out and grabbed us around the neck. Who were them guys who just tried to lay eggs on us?"

For answer, Doc Savage drew two radio messages from a pocket.

"You all saw the first one of these when it came," he said.

THE five men nodded. They had been far within the arctic regions when the first message had reached them by radio. It was very short, reading:

IN DESPERATE NEED OF YOUR HELP.

JUAN MINDORO.

Doc Savage had promptly turned the submarine southward. There was no need of lingering in the arctic, anyway. They had just completed the mission which had sent them into the polar regions — a desperate, adventurous quest for a fifty-million-dollar treasure aboard a derelict liner.

That treasure now reposed in the submarine — a hoard of wealth that had threatened to cost its weight in the blood of men.

Doc had not told his five men what meaning Juan Mindaro's mysterious message might have. They had not asked questions, knowing he would tell them in good time. Doc was sometimes as much of a mystery to his five friends as he was to the rest of the world.

They had guessed there was danger ahead, however. Several days ago, Doc had hailed a liner they chanced to pass, and had put aboard the vessel three persons who were passengers on the submarine. These three people — a famous violinist and his wife and daughter — were, with Doc and his five men, the only survivors of the grisly episode in the arctic through which they had just passed.

The radio commentator had not mentioned these three. He had not known of them. Nor would he ever know, for the polar episode was now a closed book.

The fact that Doc had transferred the three passengers to the safety of a liner showed he wanted them out of danger and told Doc's men they were headed for more trouble. They didn't mind. It was the thing they lived for. They went to the far corners of the earth to find it.

But they had not known Doc had received a second message from the same source.

Doc extended the missive. "I copied this myself a few days ago. Read it."

Crowding about, the five men read:

I HAVE BEEN FORCED TO GO INTO HIDING AT

THE HOME OF THE MAN WHO WAS WITH ME

WHEN I LAST SAW YOU. MEET ME THERE UPON

YOUR ARRIVAL. AND BE PREPARED FOR

ATTACKS ON YOUR LIFE.

JUAN MINDORO.