He shook his head. “It feels a bit like being bounced around on a rough road, that’s all.”

“And they won’t see us or hear us?”

“As long as I am holding the watch,” Isaac said, uncomfortable as he thought about Hypatia. “We had better hold on to each other, too. You may need to be touching me to stay invisible. Remember the law of unintended consequences. We do not want to change anything in the past.”

She nodded. “Do you know where and when we’re going?”

“No. But I trust my parents. So, are you ready?” Isaac asked again.

She nodded again and smiled. “It might be fun. Maybe we’ll see an amazing place and time.”

Maybe they would. In fact, Isaac thought, they almost certainly would, no matter where they went. After all, how many people were lucky enough to travel through time and space and come home again?

He smiled back. “We just have to remember what we need to do. Find that next clue.”

“Right.”

“All right, then. Hold on tight.”

Isaac wound the watch.

CHAPTER 36

Isaac and Amelie

Pumapunku, Tiwanaku Valley

Circa 1000

As the kaleidoscopic whirl begins, Isaac can feel Amelie’s tight grip on his left arm. He clutches the watch in his right fist with the snake-bracelet wrapping his arm just above, and they tumble backward through space and time—the space-time continuum, Kat had called it—and Isaac is seeing places and events from his own life that he’d seen before.

Then they’re high above a treeless, rocky plain, one side edged by snow-capped mountains, a long flat lake dotted with islands on another, and the far-off sea sparkling in the sunlight opposite the mountains. The plain and the lake draw closer and closer as if Isaac and Amelie are falling out of the sky, and he hears a small cry from Amelie as they plunge toward the earth, toward a green field in the middle of the plain, a field that is laced with narrow ribbons of water and they fall down, down, down.

Isaac shuts his eyes, sure this is the last thing he’ll ever see.

And then, a soft thump.

Isaac is lying on his back. Amelie is lying by his side, still clutching his arm. He’s not sore, not even winded. When he opens his eyes, the sky above is deep blue. The air is cold and the earth beneath his back is soft and wet. He smells fish and rotting vegetation, and when he sits up, his head swims.

“Isaac?” comes Amelie’s small voice, as she sits up. “Where are we?”

The mountains, bright with snow, form a long line in the distance to his right, a spiky high ridge. He turns and they both stand. Isaac shivers. The plain around them, a field of crops that’s rocky where it’s uncultivated, stretches away as far as he can see.

“I’m dizzy,” he says.

“Me too.”