* * * * * The mass of undead were almost upon him, the murky light glinting on menacing blades, when Cliff blew the first note. The note of sleep! He tried again, hastily. And it was the right one! At the doleful, soothing sound the undead halted in their tracks; halted--and melted into nothingness before his eyes! But now those other five in their robes of bloody red--they were charging, and even though they were unarmed, Cliff felt a stab of fear. They possessed powers beyond the human, powers a mortal could not combat. He braced himself and waited. At the bottom of the steps they stopped, ranging in a wide half-circle. The central monster--the Master--flung up his arms in a strangely terrifying gesture, and Cliff saw his carmine lips move in a chant which he could not hear. Something, a chilling Presence, hovered about him, seemed to settle upon him, cloaking him with the might of the devil himself. That unheard incantation continued, and Cliff felt a cold rigidity creeping through every fiber, slowly freezing his limbs into columns of ice. With a mighty effort of will he flung himself toward that accursed drinker of blood--and at that instant a terrific detonation rocked the ancient building, and a cloud of smoke and flame burst from the opening in the wall. Cliff was hurled from his feet, rolled over and over, and crashed against the wall by the awful concussion, the cutlas and silver horn sent whirling through the air. Dizzily he staggered to his feet, crouching defensively. Sounds came to him clearly now; the explosion must have jarred the plugs from his ears. He scanned the room; saw the unclad humans scattered everywhere, most of them lying still and unconscious. He saw Vilma rising slowly; then he looked for the monsters in red. Startled, he saw them rushing toward the opening in the wall, to vanish in its smoke-filled interior. Why did they----? Then he knew. Down there somewhere were their graves--graves rent and broken by the explosion--graves threatened by the flames--and panic had seized the vampires, fear of the death which would result with exile from their tombs! Unsteadily Cliff crossed to Vilma. She saw him coming and flung herself sobbing into his arms. He crushed her lithe form close--and another explosion, more violent than the first, sent a section of the stone floor leaping upward as though with life of its own. Clinging to Vilma, Cliff managed to maintain his footing, though the floor bucked and heaved. A snapping, booming roar--and a great chasm opened in the floor. A breathless instant--and a segment of the stone stairs, rumbling thunderously, dropped out of sight into a newly formed pit! With it went the blasphemous altar and its phosphorescent fire.