Vadesh made an elaborate shrugging motion. “But it’s not just a person I need. It’s the jewels.”

Loaf looked at Rigg and held out his hand.

Rigg wanted to say, No, they’re mine, Father gave them to me, they’re my inheritance! But he knew he had no right to keep Loaf here against his will. So he drew out the bag with the stones and handed it to Loaf.

Loaf opened the bag and poured out the jewels into his hand.

“Ah,” said Vadesh. “This one is the key to Vadeshfold.” He picked up a pale yellow stone. “With this, a human can turn off this wallfield.”

“This wallfield is only half the Wall,” said Loaf.

“The other stone isn’t here,” said Vadesh. “The one that shuts down the field protecting Ramfold.”

“The one we sold,” said Rigg, realizing.

“The one that the People’s Council stole from us,” said Loaf.

“This one?” asked Umbo. He opened his hand, and there in his palm lay a red stone. Just like the one that Rigg had entrusted to Mr. Cooper, the banker in O.

“Where did you get that?” asked Olivenko.

“After all the times we tried to break into the bank to get it back, you had it all along?” said Loaf.

Now Rigg put things together. “He found it yesterday, when we first arrived.”

“It was just lying there at the edge of the woods where we slept,” said Umbo. “I picked it up.” He turned to Rigg. “You saw me, but you didn’t even ask me what it was.”

“I figured you’d tell me when it mattered,” said Rigg. “And you did.”

“So much for Rigg always trying to be in charge of everything,” said Olivenko.

“I never said that!” said Umbo.

“Yes you did,” said Olivenko. “About a hundred times, in a hundred ways.”

“It doesn’t matter,” said Rigg. “Is that the right stone?”

Vadesh looked at it, then handed it to Loaf, pairing it with the yellow one from Vadeshfold. “These are the two you’ll need to bring down the Wall between Ramfold and Vadeshfold.”

“You put it there,” said Rigg. “For Umbo to find.”

“I did not,” said Vadesh. “I couldn’t.”

“Don’t all the expendables have a complete set of all the jewels?” asked Rigg. “This is one of yours.”

“You couldn’t use any of mine,” said Vadesh. “They can only be used by humans who grew up in the same wallfold as the jewels. They imprint on you. What would be the point of leaving one of my jewels for you to find? This jewel is from the Ramfold set.”

Vadesh spoke so confidently. Yet he seemed untroubled by the question of how the jewel got from Ramfold to this grove of trees. “Who put it there?” Rigg demanded of the others. It was plain Vadesh was not going to tell them, even if he knew, which he probably did.

“Maybe you did,” said Olivenko.

“Me?” said Rigg. “I didn’t have it!”

“Maybe you came back from the future, when you do have it, and you put it there,” said Olivenko. “Isn’t that possible?”

“Or Umbo did,” said Rigg. “And put it where he knew that he alone would find it.”

“But that would mean that in the future, I go back to Ramfold, somehow get the jewel, and then come back here and leave it for myself,” said Umbo. “Why?”

“We’ll never know,” said Loaf. “Because that version of the future is destroyed by the very fact that you now have the missing jewel, so you won’t have to go get it.”

“Why didn’t I hand it to myself, with an explanation?” asked Umbo. “At least I could have left myself a note.”

“You’ll have to take that up with yourself, later,” said Loaf. “What matters is, I have the power in my hands now to bring down the Wall and go home.” Loaf rose to his feet and faced Vadesh, looming over him. Loaf was big enough that this move no doubt intimidated most men, but Rigg didn’t imagine Vadesh was all that impressed.

“Come with me,” said Vadesh. “You can control the Wall now.”

“Where are you taking him?” demanded Rigg.

“I thought you weren’t in charge,” said Olivenko.

“I’m still his friend,” said Rigg. “A friend demands to know where you’re taking him.”

“Into the starship,” said Vadesh. “Inside the mountain.”

CHAPTER 6

Inside the Starship

“I’m coming with you,” said Rigg.

Umbo was not surprised. Rigg might talk about how he was tired of being in charge, but he would never stop thinking that everything was his business.

But Rigg was right, too. Whatever Vadesh had in mind, Loaf should not go alone with him into the mountain, into the starship. Only it wasn’t Rigg who should go with him, it was Umbo, who had been Loaf’s companion during all the time that Rigg was in captivity.

“I’ll do it,” said Umbo. “Not you.”

Rigg looked at him steadily. “Someone should stay outside, so that whatever happens in there doesn’t happen to everybody.”

“Then you stay outside,” said Umbo.

“I’m happy to stay outside,” said Olivenko. “I can wait for Param Sissaminka and explain what’s happening.”

“Good idea,” said Umbo.

“Except that first somebody needs to explain to me what’s happening,” said Olivenko.

“Umbo and I are going into the starship with Loaf and Vadesh,” said Rigg.

“For once can’t I do something without children tagging along?” said Loaf.

Umbo felt slapped.

“I think I should carry the jewels,” said Rigg.

“Whatever we’re going to do with them,” said Loaf, “I think I can do it.”

“You trusted us with the jewels before,” said Umbo. “We didn’t let you down.”

“It’s not you that I don’t trust,” said Rigg.

“It’s me,” said Vadesh. “Ram lied to him so constantly that it’s no wonder he doesn’t trust someone with the same face. I don’t care who holds the jewels.”

“Then I’ll hold them,” said Umbo.

“The last time you had them,” said Rigg, “you hid one.”

“I was experimenting with timeflow,” said Umbo.

“Why not experiment with letting a grownup do a man’s job?” said Loaf.

“And where would we find a grownup?” said Umbo.

Loaf laughed at him. “Such a youthful thing to say. Very refreshing.” He turned to Vadesh. “Lead the way.”

“I’ll wait here for Param,” said Olivenko.

Umbo felt a pang of jealousy. Completely irrational, but the thought of leaving Param alone with this handsome young scholar-soldier bothered him. So Umbo defied his own feelings and simply turned his back and walked toward the door.

“Not that way,” said Vadesh. “It’s farther in.”

“But we’re far from any mountain,” said Umbo.

“We’re already on the shoulder of the mountain,” said Vadesh, “and not all roads are on the surface of the world.”

They walked through a door in the far end of the water room, and found themselves in a huge space filled with machines of inexplicable purpose. They all seemed to be made of the same kind of impervious metal that the outside walls were made of, that the surface of the Tower of O had been made of. Umbo knew that the Tower of O had been attacked in every possible way, not by warriors, but by researchers trying to understand what it was made of. Heat was one of the many things it didn’t respond to. So how could the metal—if it was metal—be poured into molds in order to be shaped into machine parts?

And what did the machines actually make? Huge moving parts were visible, but none of the things they actually worked to make. Umbo wanted to see it moving, partly because he wanted to watch them move, and partly to see what came out of the end of each machine.

Umbo knew he was lagging behind the others, but he could hear their footsteps and they were not far ahead. He would catch up. He just wanted to figure out how this one machine worked.

And then he was aware of someone standing beside him. He turned and saw himself.

The self he saw was bloody, his ear half torn away, his arm broken, his face contorted with pain. As soon as his vision-self saw that he was looking at him, he held up his good arm and whispered, “Stay here. Do nothing.”