Those questions gave Isaac a shiver that started at his feet and shimmied itself all the way up to his shoulders. But he was glad someone finally put a voice to his fears. He wasn’t the only one who looked at Old Man Frypan, his face a mask of mystery. What must he be thinking, the only one in their company who’d had the pleasure of hanging out with Cranks?

Kletter wearily shook her head. “You all think I’m a wealth of knowledge, don’t you? I know maybe ten percent more about the world than you do, if that. But as far as I do know, in this city at least, Cranks are a thing of the past. I’ve never seen one. Not a single one.”

“So we’re safe,” Dominic declared.

That made Kletter bark a laugh that echoed off the decayed walls of the closest buildings, and she went on laughing for a solid five seconds. Then the smile swept right off her face like she’d wiped it with a rag.

“You’re not safe, boy,” she said. “You’re never gonna be safe again. Now let’s get walking.”

It was a long walk, through streets filled with trash and weeds; past buildings broken and crooked; under a sky that slowly darkened toward dusk. To Isaac, the rusted skeletons of old vehicles remained the starkest reminder that this place had once been inhabited by humans. Despite the rotted wheels and the broken glass and the faded paint, their purpose remained obvious—a carriage for people who no longer existed. Like hands and feet without a body to move them. The buildings took on a tableau of nature, as if they were mountains and hills and ridges of stone, their surfaces riddled with countless caves into the mysteries of the deep earth.

As they trudged their way along the filthy roads toward a rise of foothills scabbed with bushes and scrub oak, Isaac noticed pockets of odor that brought back the nausea of their sea voyage. Although he tried to deny it, he knew they were the smells of rotting bodies, the wet decay of flesh.

Animals, he thought, convincing himself. Just animals. It’s been too long for it to be . . . people.

Cranks! his mind screamed at him.

This spurred him to ask a question, make people talk. He addressed the distinguished members of Congress, all of whom looked like three days of rough road, as his grandpa used to say.

“What made you guys do this?”

Ms. Cowan looked at him, a little dazed from daydreaming. “Do what?”

Isaac couldn’t help his chastising expression, no matter her age. “This.” He gestured at his friends, at the city. “Go against the other Congress folks and bring us on this trip.”

Sadina’s mom shrugged. “It was the right thing to do. Sonya, famous Sonya, was Sadina’s paternal grandma. And Kletter says that means something important.”