"You've got to get us into the hall, so that we may liberate Jhanon," Shan Kar quickly told the wolf.
Nelson realized that everything was working their way. The fact of the Humanite prisoner being in that building made it possible to let Tark lead them right in there before they turned on him. Yet he had a dim suspicion that this fortunate coincidence was too fortunate! If Tark had really fathomed that their mission was to seize Kree and Nsharra—
The wolf's clear thought interrupted his uneasy speculations. "There's only one secret way to the Hall and that's by the drains of the ancients."
"We could too easily lose ourselves in that maze of tunnels," objected Shan Kar.
"Not if I guide you," Tark assured. "But the decision is yours. You can see there is no other way for you to enter Vruun."
Nelson liked the prospect less and less. But it was obviously madness for them to try entering the city openly. Unless they took the wolf's way in they must give up the whole attempt.
He said as much to Shan Kar. "We'll try it. Lefty, you can wait here if you want to."
"I'm goin'," whispered the Cockney hoarsely.
"We will swing around to enter Vruun from the north side," Tark said, "Few of the Brotherhood ever go out that way from the city."
"Why not?" Nelson demanded suspiciously.
Shan Kar answered, pointing. "The Cavern of Creation, the forbidden place, lies up there."
Nelson stared with swift interest. He saw that, north of Vruun, the level forests that encompassed the city marched up to grassy hills that were the foothills of the great northern mountains. In the face of those dark hills he glimpsed a great cavernous opening. He could see it in the dark because light came from it-a vague, unreal, quivering white glow.
The light danced and wavered, throbbing like a heart. Witch-light, ghost-light, pulsing mysteriously from that great opening!
"Yes, that is the Cavern," Shan Kar answered his thought. "The glow is of the cold fire that forbids entrance to all except the few who know the secret way."
Cold fire? Nelson felt a sharp wonder. There must be something deadly there to have inspired such awe and fear. But what?
Shan Kar said savagely, "The Cavern is a curse to L'Lan! That unholy place started the Brotherhood's lying myth that our human and beast races were there created equal."
They lost sight of that mysterious distant eye of light as they followed Tark down the forest slope. The wolf led them into the gully of a small stream-bed that ran past the north side of Vruun toward the river.
The stream-bed was empty in this dry season, its sands baked flat and hard. Its high banks hid the city from them as they approached. The wolf finally stopped and they heard his urgent thought-command. "This way — and quickly!"
They blundered after him toward a dark, mouth-like opening in the southern bank of the little gully. Tark led into the opening and Shan Kar, sword in hand, followed. Nelson and the Cockney gripped their pistols as they too stooped and went in.
They found themselves in absolute darkness. Nelson flashed his pocket-light, startling both Tark and Shan Kar.
"What is this place?" Nelson demanded.
It was a round tunnel of glassy substance. They could not have kept footing in it but for the dried sand and silt on its floor.
"These drains carry the waters from the ridges in the rainy season down beneath the city to the river," explained Shan Kar. "No man knows all their labyrinth."
"No man, but we of the Clans know," put in Tark. "I can lead you to an opening directly beneath the Hall."
Shan Kar surreptitiously pressed Nelson's wrist. It was the signal they had agreed upon and he knew what it meant. They were to stun the wolf as soon as he led them beneath the Hall of Clans. Then, swiftly and secretly, they must seize Kree and Nsharra and return.
Nsharra? Nelson felt an odd quickening of his pulse each time he thought of the witch-girl who had nearly had his life once. He hated that irrational throb of excitement.
"Still romantic," he told himself satirically. "Even ten years of Asia hasn't ground all that out of you."
Shan Kar was telling Tark, "Lead the way. But, Tark, remember that if you try to go too fast you will die very quickly."
The wolf made no reply but trotted deliberately forward up the gently slanting tunnel. The three men, stooping, followed. Soon, the tunnel forked. Tark unhesitatingly took the left turn. They followed, their pistols and the light covering him.
The tense silent progress into these ramifying tube-ways beneath Vruun began to get on Eric Nelson's nerves. He began to think he could hear a whispering echo of sound from behind them.
He told himself as he glanced swiftly backward, that he was letting his nerve slip, that he-
He did glimpse something back there in the tunnel! Blazing eyes in the gloom, eyes that were following them!
"It's a trap! We're being followed-" Nelson started to yell.
But the wolf caught his thought and acted even as the sound left his lips. Tark whirled and charged back on them with inconceivable swiftness. His hairy body was a living battering-ram that knocked the little light from Nelson's hand. The wolf crashed on through them.
"Knew it!" shrilled Lefty Wister, and triggered his automatic half-blindly as the light smashed out against the floor.
The thunderous echoes of the forty-five were deafening in the confined tunnel and Nelson heard ricochets screaming. Then Tark, who had crashed back through them to join those other eyes following them, sent his thought through the dark to them.
"We block your way to liberty! You cannot escape — lay down your weapons!"
"A trick!" raged Shan Kar. "Tark somehow managed to betray us without our knowing."
"As you planned to betray me with your lie of coming for Jhanon!" rang the wolf's thought from the darkness. "Fools, not to know that when Grih went toward Anshan at my order, he'd strike our trail and backtrail it — follow us to Vruun!"
Nelson, in a flash, realized the wolf's cunning in sending that Clawed One they had met in the forest on a direction that would cross their trail and thus tell the tiger something was wrong.
"Lay down your weapons and we shall not kill!" Tark's thought continued swiftly. "You shall be our hostages for Barin!"
For answer, Lefty Wister mouthed a curse and emptied his gun into the darkness. But again the slugs ricocheted in whining shrieks off the curved walls of the tunnel.
"They're back around the fork where your weapons can't reach them!" Shan Kar cried. "They'll arouse all Vruun! No chance now to seize the Guardian. We must escape this trap!"
Nelson, scrambling back to the fork in the tunnel, had hastily pulled a bulbous object from his pocket. He ripped out its pin.
"This will clear the way out for us!" he rasped and leaned and hurled the deadly thing around the fork of the tunnel.
"Down!" he yelled, and at the same instant heard the swift warning thought of Tark.
"An outland weapon, Grih! Out of the tunnel, quick!"
Nelson had a second to remember that Tark had seen grenades in action in Yen Shi before his own grenade exploded.
The explosion in the confined tunnel felt titanic. A giant scorching hand smashed them down flatter against the silted floor. Nelson leaped up, still dazed and shaky from the explosion, and shouted to the others. "Now — back out of here!"
They scrambled down through the tunnel, over broken shards of glass masonry the grenade had ripped from its walls. Now a dim circle of starlight ahead showed their exit.
They burst out of it into the starlit gully of the little dry stream, and tripped over a huge, striped, prostrate body. The tiger, Grih, had not escaped the tunnel quite in time and the outblast of the grenade had stunned or killed him.