direct the crowd caught and jammed in the lower approaches. He waved Toby, his assistant, toward the exit bored into the canyon wall, rushed after him at the last second.
The veteran announcer was three yards from the narrow exit when the first terrific detonation rocked the canyon from deep in the bowels of the mighty dam. The rock walls trembled.
He stared down, hypnotized into rigidity by the enormous snake-like cracks appearing in a patternless maze across the solid face of the man-made water barrier. The greenish expanse of imprisoned flood, extending for miles back of the dam, rippled and shuddered.
And suddenly, as a second shock reverberated, Lewis' widened eyes narrowed on the black-hooded, cloaked figures emerging from a leaking sluice slot at the dam's base, running for shelter. A moment later, with three more thunderous explosions shattering the masonry, the center of the dam split open into an enormous, writhing V.
A harsh, angry roar arose drowning out the rumble of the rocking blasts, and the strangled water poured through the split, tearing away huge pieces of the dam, widening the vital opening.
The two fleeing black-robed figures disappeared, whirled away in the first rush of the flood that blotted out the power houses and buildings at the foot of the dam as though by, magic in a hellish cataract of thundering destruction.
The churning water rushed on, sweeping everything in its path. The helpless spectators, workmen and soldiers caught beneath the rising tide of the whirling, serpentine monster of death, were gone like straws, their despairing cries lost utterly in the horrifying roar of the plunging flood.
Mort Lewis swayed dizzily, leaped for the dangerous safety of the narrow exit at the end of the completely crumpling dam. He lunged halfway through the tunnel opening, was knocked down as part of the wall gave way.
Rocks and shale pounded down on his twisted legs, pinioned him helplessly to the stone floor. He lay there writhing, sweating in agony, while behind him the snarling torrent drowned out his shouting, fading voice.
Chapter Two.
Red Warning
Lowering purplish storm clouds had hovered menacingly over New York City all day, seemingly caught and held stationary by the sharp spires and pinnacles of the towering skyscrapers. At three o'clock in the afternoon the storm hadn't broken yet, and the spasmodic rumble of thunder was just beginning to become annoying over radios in crackling static.
But it wasn't storm interference that broke in upon the swing music floating from the hidden radio in the large Moorish reception room of the stately Fifth Avenue residence of Mr. Frank Havens, the nationally known publisher. It was the announcer's smooth voice cutting in from Radio City:
"Ladies and gentlemen, through the facilities of the National Broadcasting Company, you are about to hear the President of the United States speak from Rock Canyon Dam, Arizona, where he will formally open the largest irrigation system in the world. One moment, please—"
As the fading strains of the National Anthem, played by the U. S. Marine Band, swelled into the big, gaily crowded reception room, Muriel Havens stopped dancing and smiled whimsically up into the lean, tanned face of Richard Curtis Van Loan.
"Something official like that would have to break into my afternoon tea-dance," she protested with a little laugh, and started to signal a butler to dial in another program.
Dick Van Loan stopped her with a quick shake of his head and moved with her nearer the wide window where the radio was camouflaged in a flower-covered wall table.
"Mind if I listen to him?" he asked politely, and added, "The daughter of Frank Havens should be able to inflict the President's voice on her guests for a few min—"
His bantering words broke off abruptly as his sharp eyes flicked to the window.
Out across Central Park, rising high above the skyscrapers of the Roaring Forties to the south, blinking red lights on Frank Havens' towering Clarion Press Building gleamed now, flashing warningly, vividly against the purplish background of foreboding storm clouds.
The Phantom's signal! Neither exclamation nor tremor betrayed the vitalizing shock that whipped Dick Van Loan's nerves into tensed alertness. His signal—from Frank Havens—Around him the gay party went on, heedless and merrily ignorant of the dire call. Even Muriel Havens, the nationally powerful publisher's beautiful daughter, had no inkling of the grim Phantom drama being signaled in by those rapidly winking lights atop her father's Clarion tower.
Dick Van Loan's cryptic smile gave no hint of the driving turmoil seething within him as he deciphered that flashing code message:
Calling the Phantom—Come to my office—
Hurry—This is a murder call—Havens—
Calling the Phantom—
The dots and dashes kept on winking ominously, would continue to blink that secret message until the Phantom himself contacted Frank Havens. Van Loan damned himself mentally. He'd been idling here, dancing, unalert to that urgent message.
But before his brain could hit upon an acceptably logical excuse to offer Muriel Havens for an abrupt departure, the familiar voice of the veteran radio announcer, Mort Lewis, broke in upon his consciousness:
"—From Rock Canyon Dam—The President of the United States!"
Then the President's warm voice: "My friends—"
Dick Van Loan's eyes narrowed at the sharp click that interrupted the President's kindly greeting.
The next instant, as the first chilling words of that strange unannounced metallic voice came brassily over the air, Van stooped low over the radio table, his tensed fingers twisting off the volume. He motioned Muriel Havens away, dialed the icy flow of words until he alone in the room could hear:
"—the Imperator of the Two Americas speaking for the Invisible Empire. Rock Canyon Dam will be destroyed in—one hundred seconds. Future public disasters will follow—Sixty seconds—I, the Imperator, have spoken!"
Grimly, his knuckles white against the dial, Dick Van Loan spun the volume on full as the icy metallic voice stopped with a brittle snap that was like glass broken by a hammer blow. But now only a vague rumbling sound and the crackle of distant static came from the suddenly stilled station.
Tight-lipped, Van turned down the power to normal volume, dialed in a dance orchestra on a minor local station, and rose to face Muriel. No use disrupting her afternoon party with this new, grimly spectacular radio mystery. Damage enough, that millions of listeners had heard that dire, threatening voice.
"Something went wrong with the President's address," he said to her with a convincing smile of apology.
"I'm a very hard-boiled stockholder in that broadcasting company, so you won't mind. Muriel, if I run off from your very pleasant soiree to see what's happened?"
How much she minded was evident in her gently veiled, disappointed gaze as she let him go. But it was not a polite lie that Dick Van Loan used to excuse himself from the Havens home.
He did own stock in the
