Dorothy felt a chill down the back of her neck. Part of her wanted to tell Roman to leave it. She didn’t think she was strong enough to take anything else just now. She could deal with the future when she’d saved Ash and stopped Mac and convinced her friends to trust her, again.

But she’d always been curious, and she couldn’t stop herself from saying, “You know why our world falls apart?”

Roman gazed back at her. “Before I started researching time travel with the Professor, I was working on a computer program,” he said. “It was supposed to help predict upcoming earthquakes. My research was ultimately inconclusive, but the data seemed to indicate that there was a relationship between travel through an anil and the movement of tectonic plates.”

“I don’t understand,” Dorothy said, blinking at him. She had a sudden memory, Zora and Ash and the others gathered together in the schoolhouse where they all used to live, trying to explain earthquakes to her. “Tectonic plates? That’s something to do with earthquakes, isn’t it?”

Roman didn’t seem to register her interruption. “I’d been paying particular attention to the earthquakes we’ve experienced over the last year. They’ve become more frequent. Can you think of any reason why that might be happening?” He paused and looked up, as though waiting for Dorothy to catch on. When she said nothing, he added, “Dorothy, the earthquakes are caused by time travel.”

Dorothy felt the edge of her lip twitch. It was a tick, smiling to cover her nerves. “That’s not possible.”

“I keep going over the data and it remains, stubbornly, consistent. The dates and the times and the Richter scale numbers, they all add up to one clear conclusion.” Roman released a short, bitter laugh. “It’s honestly amazing to me that no one else has put it together.”

“Roman, you hear what you’re saying, don’t you?” The smile had dropped from Dorothy’s mouth. She licked her lips. “If the earthquakes were caused by time travel, that would mean that we caused them. You and me.”

Roman stared back at her, not blinking.

“That’s not possible!” she said again. Her heart was beating very fast inside her chest.

“I wanted to be wrong. But the numbers don’t lie.”

Dorothy shook her head as cold fear oozed through her, leaving her numb. She thought of the neighborhood they’d gone back in time to loot, that little old woman and her dog, Pumpkin. Roman’s sister.

The earthquake that had occurred after they’d left that time had killed all of them.

Oh God . . .

She sunk to Roman’s bed, her entire body feeling, suddenly, very heavy. She lifted a hand to her mouth, thinking of all the times they’d traveled back into the past, all the silly, frivolous things they’d done.

How many lives had been lost because of them?