Param nodded and disappeared.

Umbo kept his eyes on the Visitors; he could not afford to be looking away at the moment Param appeared. They’d only have a few second before the mice would react. Perhaps by killing her again.

Param appeared. The Visitor who had been speaking stopped and inclined her head to look at Param, then said something to her.

Param held up her hand in a gesture of silence. Wait. And then she was blurting out something and suddenly her fist was extended. It was the signal. Umbo took hold of her and dragged both of them backward in time.

Param dropped in a heap to the ground. The flyer was gone, so her position on the ramp had become a point in midair.

But she was unhurt, and in this particular timeframe there wasn’t a soul here. Not even the mice.

“I think I may have brought us back a little earlier than I wanted,” said Umbo.

“Or later,” said Param. “I don’t know if it will matter.”

They walked back toward the camp in realtime.

Whatever doubts he might have had, Umbo found as they approached that it was the very night when they had left. There was Loaf, and there was Olivenko, exactly as they had been; and there were Umbo and Param, asleep.

“No,” whispered Umbo when Param seemed about to speak. “Say nothing if you can help it, not till our earlier selves are gone. We don’t want to let them see us. It complicates things sometimes.”

“I was going to say,” said Param softly, “that you got us here within half an hour of the time we left.”

“In the wrong direction,” said Umbo.

“Before is better than after,” said Param.

They waited in sliced time then, wordless until the sleeping version of themselves woke up, packed quickly, and set out, disappearing moments after they started walking.

Was that the same way it had been earlier? Or did Umbo remember that Param started splitting time before they walked away from camp. Was it possible that they had inadvertently changed something in the past? Might they have therefore bifurcated themselves, so that a complete duplicate set of themselves would be wandering around, thinking they were the real Umbo and Param?

Maybe they were.

Param and Umbo walked back into camp.

“What did you learn?” asked Loaf.

Umbo had forgotten that Loaf and Olivenko had been awake when they left. “The Visitors came but I didn’t have much chance to hear them.”

“We saw mice getting in their flyer,” said Param. “They moved sluggishly. As if they were sick.”

“We thought, what if the mice developed a disease to carry back to Earth?” said Umbo. “Something the humans of Earth can’t defend against.”

“So instead of learning the answer to your ‘what if,’ so you could decide whether to intervene,” said Loaf, “you intervened.”

When he put it that way, it didn’t seem like such a good idea.

“Did you know that any mice were sick?” asked Loaf.

“They looked sick,” said Param defiantly.

Umbo was grateful that she was backing him up on this; she could so easily have laid all the blame on him. In fact, he suspected that the blame was his. But then, to blame him would imply that she had been taking orders from him. Her pride could never let her do that.

“What did your intervention consist of?” asked Olivenko.

“I told them that the mice on their ship were smart and deadly,” said Param, “and they needed to kill every last one of them so they’d return to Earth with none aboard.”

“And the mice didn’t stop you,” said Loaf.

“I’m not sure any of them saw that she was there,” said Umbo. “Param delivered her message so quickly.”

“So you’re going to get away with having a whole bunch of half-human mice slaughtered,” said Loaf. “What a relief.”

“What if having the mice reach Earth was the only way to save Garden?” asked Olivenko.

“Then next time around,” said Umbo, “we’ll let them go.”

“What next time?” asked Loaf. “Maybe next time, the mice won’t alter Knosso’s genes, or give you your real father. What if they completely undo us so that next time we won’t interfere in their plans?”

“You forget,” said Umbo. “They can’t go back in time.”

“They can write letters,” said Loaf, “and send them back, and read them, and act on them.”

“On your information-gathering mission, did you learn anything to guide us on how to prevent the Visitors from hating and fearing us?” asked Olivenko.

“We were too busy trying to save the lives of all the humans on Earth,” said Param.

“I thought saving the lives of all the humans on Garden was a slightly higher priority,” said Olivenko.

“Isn’t it enough to have learned what the mice were doing?” asked Umbo.

Olivenko shook his head. “You saw mice getting on the Visitors’ flyer, and you assumed that they were doing what you already thought they were doing. You assumed that your previous guesses were right. But you had no evidence.”

“Are you a lawyer now?” asked Param.

“I try not to be part of indiscriminate murder,” said Olivenko. “Which is pretty much what you just did. Will do.”

“Maybe warning the Visitors will prove to them that they shouldn’t get us all killed,” said Umbo. “Maybe we just saved Garden and Earth.”

“Think!” said Loaf. “We know they destroyed Garden nine times—before the half-human mice were ever created. So how can warning them about the mice stop them from doing something they repeatedly did before there were ever any mice at all?”

Why hadn’t Umbo thought of all this himself? Why had he just . . . acted? For that matter, why hadn’t Param thought of all these objections even if for no other reason than to undercut Umbo? Why, this time of all possible times, did Param actually cooperate with him?

Umbo saw the way Loaf looked at him, then glanced languidly at Param, then back at Umbo, and he knew what Loaf was really saying. You were showing off, Umbo. You were impressing the girl. You weren’t thinking with your head.

“So maybe we blew it and maybe we didn’t,” said Umbo. “Or maybe we saved the world. Let’s see how things turn out.”

“If the mice don’t kill us all as soon as they find out what you’ve done,” said Loaf.

“For all we know, the future mice are putting poison in our food right now,” said Olivenko.

“Then we’ll die,” said Umbo. “But you don’t know we were wrong any more than we know we were right. So back off!”

“What we don’t know hasn’t killed anybody,” said Loaf.

“Or saved anybody,” said Umbo. “Or accomplished anything at all.”

“There are so many mice,” said Param. “Who’ll even notice they’re gone?”

“There are so many humans,” said Loaf savagely. “So many peasants. So many of our enemy. So many of the poor. So many ugly people, so many stupid people, so many people who aren’t as good as me. Who’ll miss a few dozen or hundred or million, if my actions happen to kill them?”

Param reeled at the accusation. She looked about to cry.

She disappeared.

“Now look what you’ve done,” said Umbo.

“You foolish boy,” said Loaf. “You’re more upset over my hurting Param’s feelings than you are about the murders you just committed without any evidence that you were accomplishing anything.”

Umbo knew that Loaf was right. Excruciatingly, humiliatingly right. And it was Loaf, of all people, whose high opinion Umbo wanted. Needed to deserve.

In his anguish, Umbo cried out, “I’m just a kid!”

His words hung in the air. Nobody said anything.

Param returned to view. “I’m not running away from this,” she said.

“Well, it’s nice to see that somebody’s growing up,” said Loaf.

Param glanced at Umbo, saw the tears on his face. “We did what we thought was right,” she said. “And it was a smart plan. And Umbo thought of it, and I agreed with it, and we did it. And he loves you as much as I love my father. So why can’t you show him a little understanding. Isn’t that what fathers are supposed to do?”