Tom looked upstream, figuring it probably flowed close to the place where Naomi had been taken, then presumably up the side of the same hills on which their plane had broken its spine. There was barely a trickle of lifeless water in the bottom now, but looking at the steep and eroded banks was enough to show how fiercely it flowed during the rains.

Alice approached him and said, “Shen wants you and me to go with them to follow the creek to the river and check it out.”

“Sure.”

They stepped through the maze of resting bodies to where Shen and Joel were standing looking over the creek, Shen explaining something, Joel displaying the superficial level of interest Tom had seen in footage of politicians being shown around factories.

Shen turned as they reached them. “Ready?”

Joel was quick to add, “You don’t need to come if you want to rest. I’m sure Shen and me can recon the river.”

“I’m sure you could,” said Alice.

The four of them followed the creek bed through a couple of bends, the air seeming to become more febrile, pulsing with life, the closer they got to the river itself. And when the strip of sleek muddy water appeared up ahead, there was nothing inviting or refreshing about it.

Shen climbed up the bank of the creek, onto a small point formed by its convergence with the river. They followed him, but it was instantly clear that they wouldn’t be getting the boats on this river.

It was just about wide enough, but only a narrow channel looked deep enough, and it was strewn with rocks. A short distance downstream a tree had fallen across it too.

Tom checked his watch, estimating they probably had six or seven hours of daylight left. If there were no major obstacles, there was a chance they could make the distant low hills by the end of the day, but it was more likely they’d have to make camp somewhere tonight, rather than risk walking in darkness.

It was Joel who broke the silence, saying, “I always thought this boat plan of yours was crazy.”

He’d addressed the comment to Tom, but Tom only looked back at him, and it was Shen who said, “We always knew the river might not be navigable.”

“So what do you propose now?”

“We follow it until it is, then we launch the boats.” He pointed downstream. “We’re heading for a gap in the hills. Beyond them, there’s a better chance.”

Joel shook his head doubtfully, and looked at the sluggish water in front of them. “I have to say I’m not convinced, looking at this.”

With remarkable good humor, Shen said, “There’s one thing we can say with absolute certainty, Joel—rivers don’t get narrower. So there’s no alternative. It might take us a day to reach open water, it might take two, but we head downriver.”