Monk let out a bellow that would have shamed the beast he resembled. He stamped up and down. He waved his huge, corded arms that were inches longer than his legs.

"Somebody run a whizzer on me!" he howled. "Whoever if was, I'll wring his neck! I'll pull off his ears! I'll give — "

"You'll be in a cage at the zoo if you don't learn the manners of a man!" waspish Ham said bitingly.

Monk promptly stopped his apelike prancing and bellowing. He looked steadily at Ham, starring with Ham's distinguished shock of prematurely gray hair, and running his little eyes slowly down Ham's well-cared-for face, perfect business suit, and small shoes.

Suddenly Monk began to laugh. His mirth was a loud, hearty roar.

At the gusty laughter, Ham stiffened. His face became very red with embarrassment.

For all Monk had to do to get Ham's goat was laugh at him. It had all started back in the war, when Ham was Brigadier General Theodore Marley Brooks. The brigadier general had been the moving spirit in a little scheme to teach Monk certain French words which had a meaning entirely different than Monk thought. As a result, Monk had spent a session in the guardhouse for some things he had innocently called a French general.

A few days after that, though, Brigadier General Theodore Marley Brooks was suddenly hauled up before a courtmartial, accused of stealing hams. And convicted! Somebody had expertly planted plenty of evidence.

Ham got his name right there. And to this day he had not been able to prove it was the homely Monk who framed him. That rankled Ham's lawyer soul.

Unnoticed, Doc Savage had reached over and turned on the ultra-violet-light apparatus. He focused it on the pieced-together window, then called to the others: "Take a look!"

The message on the glass had been changed!

There now glowed with an eerie blue luminance exactly eight more words than had been in the original message. The communication now read:

Important papers back of the red brick house at corner of Mountainair and Farmwell Streets

"Hey!" exploded the giant Renny. "How — "

With a lifted hand, a nod at the door, Doc silenced Renny and sent them all piling into the corridor.

As the elevator rushed them downward, Doc explained: "Somebody decoyed you upstairs so they could get away, Monk."

"Don't I know it!" Monk mumbled. "But what I can't savvy is who added words to that message?"

"That was my doing," Doc admitted. "I had a hunch the sniper might have seen us working with the ultra-violet-light apparatus, and be smart enough to see what it was. I hoped he'd try to read the message. So I changed it to lead him into a trap."

Monk popped the knuckles in hands that were near as big as gallon pails. "Trap is right! Wait'll I get my lunch shovels on that guy!"

Their taxi was still waiting outside. The driver began a wailing: "Say — when am I gonna get paid? You gotta pay for the time I been waitin' — "

Doc handed the man a bill that not only silenced him, but nearly made his eyes jump out.

North on Fifth Avenue, the taxi raced. Water whipped the windshield and washed the windows. Doc and Renny, riding outside once more, were pelted with the moisture drops. Renny bent his face away from the stinging drops, but Doc seemed no more affected than had he really been of bronze. His hair and skin showed not the least wetness.

"This red brick house at the corner of Mountainair and Farmwell Streets is deserted," Doc called once. "That's why I gave that address in the addition to the note."

Inside the cab, Monk rumbled about what he would do to whoever had tricked him.

A motorcycle cop fell in behind them, opened his siren, and came up rapidly. But when he caught sight of Doc, like a striking figure of bronze on the side of the taxi, the officer waved his hand respectfully. Doc didn't even know the man. The officer must have been one who knew and revered the elder Savage.

The cab reeled into a less frequented street, slanting around corners. Rows of unlighted houses made the thoroughfare like a black, ominous tunnel.

"Here we are!" Doc told their driver at last,

Ghostly described the neighborhood. The streets were narrow, the sidewalks narrower; the cement of both was cracked and rutted and gone entirely in places. Chugholes filled with water reached half to their knees.

"You each have one of Monk's gas bombs?" Doc asked, just to be sure.

They had.

Doc breathed terse orders of campaign. "Monk in front, Long Tom and Johnny on the right, Renny on the left. I'll take the back. Ham, you stay off to one side as a sort of reserve if some quick thinking and moving has to be done."

Doc gave them half a minute to place themselves. Not long, but all the time they needed. He went forward himself.

The red brick house on the comer had two ramshackle stories. It had been deserted a long time. Two of the three porch posts canted crazily. Shingles still clung to the roof only in scabs. The windows were planked up solid. And the brick looked rotten and soft.

The street lamp at the corner cast light so pale as to be near nonexistent.

Doc encountered brush, eased into it with a peculiar twisting, worming movement of his powerful, supple frame. He had seen great jungle cats slide through dense leafage in that strangely noiseless fashion, and had copied it himself. He made absolutely no sound.

And in a moment, he had raised his quarry.

The man was at the rear of the house, going over the back yard a foot at a time, lighting matches in succession.

He was short, but perfectly formed, with a smooth yellow skin, and a seeming plumpness that probably meant great muscular development. His nose was curving, slightly hooked, his lips full, his chin not particularly large. A man of a strange race.

The ends of his fingers were dyed a brilliant scarlet.

Doc did not reveal himself at once, but watched curiously.

The stocky, golden-skinned man seemed very puzzled, as indeed he had reason to be, for what he sought was not there. He muttered disgustedly in some strange clucking language.

Doc, when he heard the words, held back even longer. He was astounded. He had never expected to hear a man speaking that language as though it were his native tongue. For it was the lingo of a lost civilization!

The stocky man showed signs of giving up his search. He lit one more match, putting his box away as though he didn't intend to ignite more. Then he stiffened.

Into the soaking night had permeated a low, mellow, trilling sound like the song of some exotic bird. It seemed to emanate from underfoot, overhead, to the sides, everywhere — and nowhere. The stocky man was bewildered. The sound was startling, but not awesome.

Doc was telling his men to beware. There might be more of the enemy about than this one fellow.

The stocky man half turned, searching the darkness. He took a step toward a big, double-barreled elephant rifle that leaned against a pile of scrap wood near him. It was of huge caliber, that rifle, fitted with telescopic sights. The man's hand started to close over the gun. And Doc had him! Doc's leap was more expert even than the lunge of a jungle prowler, for the victim gave not even a single bleat before he was pinned, helpless in arms that banded him like steel, and a hand that cut off his wind as though his throat had been poured full of lead.

Swiftly, the others came up. They had found no one else about.

"I'd be glad to hold him for you!" Monk suggested hopefully to Doc. His furry fingers opened and shut.

Doc shook his head and released the prisoner. The man instantly started to run. But Doc's hand, floating out with incredible speed, stopped the man with a snap that made his teeth pop together like clapped hands.

"Why did you shoot at us?" Doc demanded in English.