They walked to the edge of the water. Matt followed an ancient impulse and picked up a smooth rock and spun it out over the water’s surface. It went a long way between skips, almost to the horizon.

“Are we far enough away to talk?”

“I don’t know. That she suggested we leave makes me suspicious. But yeah. What do you think?”

“That’s what I was going to ask you.”

“You’re clear on the Jesus part?”

“That was just to get my attention?”

“And confidence. Some of those guys look pretty strange.”

“Demonic. Why do you think they only appear in dreams?”

“Well, La can’t read our thoughts,” he said.

“She can’t invade our dreams, either. So they’re more powerful than her, that way.”

“But they can’t physically intercede. I think that’s because they’re still in our future. Just my guess. They can only send information back, not solid matter.”

There was a long pause, just the quiet lapping of the water. “Does that mean . . . we’re never going back? It really is impossible?”

He threw out another stone. It sank after one skip, “I’m trying to recall the exact wording.”

“They said they had to catch up with us. That doesn’t sound like they’re in our future. Could it mean distance?”

“I don’t know. But distance is ourproblem. After a few more jumps, we’ll be too far from Earth to return in one lifetime.”

Staring into the water, she shook her head sadly. “We’d never want to go back there, anyhow.”

She stood closer to him, her shoulder touching his arm. He put his arm around her, and it was a good thing it was his left.

Where the stone had sunk, a huge creature surged out of the water, bigger than a car, all claws and wriggling feelers. A stink of rotten vegetation.

Matt fired at it twice; the second bullet trilled off in a ricochet. Then he remembered what La had said, and pulled Martha to the ground.

When the pressor beam went over them, it felt like a hot wind. It parted the water and hit the creature with explosive force, flipping it over, exposing dozens of wriggling legs.

“Come back,” La’s amplified voice shouted. They had figured that out, and were back on their feet, running hard.

They were both gasping huge, ragged breaths by the time they collapsed on the ramp. It lifted them up, not too slowly.

La was standing, looking out over the water. “That thing was mechanical,” she said. “Maybe a defensive robot.”

“Maybe a fun amusement-park thing,” Matt said, panting. “God knows what amused the people back then. Up then. Whatever.”

“It might be a hundred thousand years old,” La said, “Two hundred thousand. Can you imagine a self-repairing machine lasting for so long?”

“Maybe it’s not self-repairing,” Matt said. “We just haven’t met the people who maintain it.”

“They’re extremely well hidden. What are they hiding for?”

“From,” Martha said quietly. “What are they hiding from, that they need a monster like that?”

“An excellent point. Perhaps we should move along.”

“We should be safe in here,” Matt said, stalling. “We ought to wait and see what happens.”

La gave him an inscrutable look. “Matt, this science could be as far ahead of mine as mine is from primates learning to use sticks. I’m not sure we care to test what they can do.”

He looked at Martha and nodded slowly. “Can’t fight the logic of that. Except that futuristic science is exactly what we’re looking for. Maybe they havemastered backward time travel, and that’s where they all are. Vacationing back in the good old days.”

“This is not a time to joke. We should push the button and get out of here.”

“We could get out of the immediate vicinity by taking off and going into orbit.”

“That would not get us out of danger. Even in my time, it would be trivially easy to knock this thing out of orbit.”

Matt had run out of counterarguments. “You’re right, of course. Let’s strap in, Martha.”

“How far are we going this time?”

“A couple of hundred thousand miles. From Earth, that would have been cislunar space, closer than the Moon. And 3.5 million years.”

“Earth will be a lot different?”

“Maybe better.” He waited for the click of her harness. “Let’s go see.”

Out of the gray swirl, the man who had been Jesus. He was dressed in something like medieval mail. The others were behind him, similarly attired. “Come to Earth as quickly as possible. We’ll find you.”

When the gray faded, they reappeared in a spot apparently closer to the Earth than the Moon. At least the Earth was larger than Matt remembered seeing it in pictures from the lunar surface. They both unhooked and floated over toward the screen.

“There’s a little bit of green.” Martha pointed.

“Let’s go down and check it out.”

“It hardly seems worth the trouble.” La peered at the mostly gray globe. “Just push the button again.”

“We haveto go to Earth!”

La looked at Martha in an impatient way. “All right.” She gestured. “Get ready for acceleration.”

When Matt and Martha were strapped in, La turned to look their way and nodded.

Handcuff-style shackles snapped shut over their wrists.

“You haveto go? Did your ghostly dream friends tell you that?”

“Shit,” Matt said.

“It’s true that I don’t have any unusual powers over you when you’re outside the ship. But a directional microphone isn’t exactly magic.

“So Jesus and some demons are going to ‘catch up with you.’ Do they claim to have a backward time machine?”

“They just said they could help us.”

“That’s a pity. That really is. Because, of course, the time machine doesn’t work if I push the button via pressor field.”

“I’ll go with you,” Matt said. “Just land long enough for them to find her.”

“No!” Martha said.

“For some reason, I doubt your sincerity. Let me show you what I cando with a pressor field.”

Matt’s breath flew out of his lungs. It was as if there were hundreds of pounds of pressure on his chest. He could see the rictus of pain on Martha’s face. Just as he was about to black out, the pressure was suddenly gone. He heaved forward, coughing, and the right shackle opened.

“She’ll be dead soon. Push the button.”

If La had waited one more second before shackling them, Matt would have been helpless. When he buckled the harness, he’d realized the pistol was still in its special pocket, pressing painfully against his ribs, and he had been about to move it to the pants pocket.

Now, bent over, La couldn’t see him slip the pistol out. He slammed the nose of it up against the time machine box. “Hair trigger!” he gasped. “Don’t even think of it.”

“Oh. So you’ll let her die?”

“If she dies, I’ll blow this thing to pieces. In fact, I’ll do it on the count of three seconds anyhow. Two . . . one . . .”

“All right.” Martha started wheezing and coughing. “That was reasonably intelligent.”

“Take us to Earth right now. If I start to fall asleep—”

“You’ll pull the trigger, sure. I’ve seen a thousand times more movies than you have.” There was a slight surge of acceleration. “I suppose we should go back to that obelisk. Or whatever’s there after 3.5 million years.”

“Maybe they can help you. Show you how to use the time machine without me.”

“Sure. It isthe future, and he isJesus. Maybe Santa Claus is with him. Just stay awake for the next ninety-two minutes.”

“Santa Claus?” Martha said.

The obelisk was still there, shining in the low winter sun, but it was tilted about ten degrees out of true. “Earth was supposed to go through a comet storm,” La said, “about a half million years ago, if our predictions were accurate. It’s a wonder the thing’s still standing.”

The ground was a jumble of broken metal and rock. La landed gingerly and put the ramp down. “Here you are. My part of the bargain.”