Ennis then spun toward the main, lighted tunnel, Campbell close behind him. They recoiled suddenly into the darkness of the branching way, as they heard hurrying steps out in the lighted passage. Flattened in the darkness against the wall, they saw several of the gray-hooded members of the Brotherhood hasten past them from above, hurrying toward the gathering-place.
"The guards and robe-issuers we saw above!" Campbell said quickly when they were passed. "Come on, now."
He and Ennis slipped out into the lighted tunnel and hastened along it after the others.
Boom of thundering ocean over their heads and rising and falling of the tremendous chanting ahead filled their ears as they hurried around the last turns of the tunnel. The passage widened, and ahead they saw a massive rock portal through whose opening they glimpsed an immense, lighted space.
Campbell and Ennis, two comparatively tiny gray-hooded figures, hastened through the mighty portal. Then they stopped. Ennis felt frozen with the dazing shock of it. He heard the detective whisper fiercely beside him.
"It's the Cavern, all right—the Cavern of the Door!"
They looked across a colossal rock chamber hollowed out beneath the floor of ocean. It was elliptical in shape, three hundred feet by its longer axis. Its black basalt sides, towering, rough-hewn walls, rose sheer and supported the rock ceiling which was the ocean floor, a hundred feet over their heads.
This mighty cathedral hewn from inside the rock of earth was lit by a soft, white, sourceless light like that in the main tunnel. Upon the floor of the cavern, in regular rows across it, stood hundreds on hundreds of human figures, all gray-robed and gray-hooded, all with their backs to Campbell and Ennis, looking across the cavern to its farther end. At that farther end was a flat dais of black basalt upon which stood five hooded men, four wearing the blazing double-star on their breasts, the fifth, a triple-star. Two of them stood beside a cubical, weird-looking gray metal mechanism from which upreared a spherical web of countless fine wires, unthinkably intricate in their network, many of them pulsing with glowing force. The sourceless light of the cavern and the tunnel seemed to pulse from that weird mechanism.
Up from that machine, if machine it was, soared the black basalt wall of that end of the cavern. But there above the gray mechanism the rough wall had been carved with a great, smooth facet, a giant, gleaming black oval face as smooth as though planed and polished. Only, at the middle of the glistening black oval face, were carven deeply four large and wholly unfamiliar characters. As Ennis and Campbell stared frozenly across the awe-inspiring place, sound swelled from the hundreds of throats. A slow, rising chant, it climbed and climbed until the basalt roof above seemed to quiver to it, crashing out with stupendous effect, a weird litany in an unknown tongue. Then it began to fall.
Ennis clutched the inspector's gray-robed arm. "Where's Ruth?" he whispered frantically. "I don't see any prisoners."
"They must be somewhere here," Campbell said swiftly. "Listen——"
As the chant died to silence, on the dais at the farther end of the cavern the hooded man who wore the triple-jeweled star stepped forward and spoke. His deep, heavy voice rolled out and echoed across the cavern, flung back and forth from wall to rocky wall.
"Brothers of the Door," he said, "we meet again here in the Cavern of the Door this year, as for ten thousand years past our forefathers have met here to worship They Beyond the Door, and bring them the sacrifices They love.
"A hundred centuries have gone by since first They Beyond the Door sent their wisdom through the barrier between their universe and ours, a barrier which even They could not open from their side, but which their wisdom taught our fathers how to open.
"Each year since then have we opened the Door which They taught us how to build. Each year we have brought them sacrifices. And in return They have given us of their wisdom and power. They have taught us things that lie hidden from other men, and They have given us powers that other men have not.
"Now again comes the time appointed for the opening of the Door. In their universe on the other side of it, They are waiting now to take the sacrifices which we have procured for them. The hour strikes, so let the sacrifices be brought."
As though at a signal, from a small opening at one side of the cavern a triple file of marchers entered. A file of hooded gray members of the Brotherhood flanked on either side a line of men and women who did not wear the hoods or robes. They were thirty or forty in number. These men and women were of almost all races and classes, but all of them walked stiffly, mechanically, staring ahead with unseeing, distended eyes, like living corpses.
"Drugged!" came Campbell's shaken voice. "They're all drugged, and don't know what is going on."
Ennis' eyes fastened on a small, slender girl with chestnut hair who walked at the end of the line, a girl in a straight tan dress, whose face was white, stiff, like those of the others.
"There's Ruth!" he exclaimed frantically, his cry muffled by his hood.
He plunged in that direction, but Campbell held him back.
"No!" rasped the inspector. "You can't help her by simply getting yourself captured!"
"I can at least go with her!" Ennis exclaimed. "Let me go!"
Inspector Campbell's iron grip held him. "Wait, Ennis!" said the detective. "You've no chance that way. That robe of Chandra Dass' you're wearing has a double-star badge like those of the men up there on the dais. That means that as Chandra Dass you're entitled to be up there with them. Go up there and take your place as though you were Chandra Dass—with the hood on, they can't tell the difference. I'll slip around to that side door out of which they brought the prisoners. It must connect with the tunnels, and it's not far from the dais. When I fire my pistol from there, you grab your wife and try to get to that door with her. If you can do it, we'll have a chance to get up through the tunnels and escape."
Ennis wrung the inspector's hand. Then, without further reply, he walked boldly with measured steps up the main aisle of the cavern, through the gray ranks to the dais. He stepped up onto it, his heart racing. The chief priest, he of the triple-star, gave him only a glance, as of annoyance at his lateness. Ennis saw Campbell's gray figure slipping round to the side door.
The gray-hooded hundreds before him had paid no attention to either of them. Their attention was utterly, eagerly, fixed upon the stiff-moving prisoners now being marched up onto the dais. Ennis saw Ruth pass him, her white face an unfamiliar, staring mask.
The prisoners were ranged at the back of the dais, just beneath the great, gleaming black oval facet. The guards stepped back from them, and they remained standing stiffly there. Ennis edged a little toward Ruth, who stood at the end of that line of stiff figures. As he moved imperceptibly closer to her, he saw the two priests beside the gray mechanism reaching toward knurled knobs of ebonite affixed to its side, beneath the spherical web of pulsing wires.
The chief priest, at the front of the dais, raised his hands. His voice rolled out, heavy, commanding, reverberating again through all the cavern.
5. The Door Opens
"Where leads the Door?" rolled the chief priest's voice.
Back up to him came the reply of hundreds of voices, muffled by the hoods but loud, echoing to the roof of the cavern in a thunderous response.
"It leads outside our world!"
The chief priest waited until the echoes died before his deep voice rolled on in the ritual.
"Who taught our forefathers to open the Door?"
Ennis, edging desperately closer and closer to the line of victims, felt the mighty response reverberate about him.