Ambrose ran a hand lightly along the gray wall, leaving a faint finger trail in the grime. “The bottom…”

Mistletoe waited for him to blurt out the rest of his delayed understanding, but that was all he said. So she gave him the short history of subcanopy life she’d pieced together from conversations with Jiri and Aunt Dita.

“Plasteel was invented. Buildings started to hit the clouds. Nobody who could afford a place up high wanted to live way down low. So the bottom floors were for people like me and Jiri, but after a while people like you decided it was too dangerous having rich people and poor people in the same building. They evacuated the first thirty stories and filled in the floors with extra plasteel support beams so nobody could move back in. Eventually they were all like that. We built houses up the sides of your buildings; you laid down the canopy. It was all just a big back and forth.”

“There were riots,” Ambrose said gently, like he was correcting a well-meaning but misguided child.

Mistletoe imagined elbowing him in the face and tossing him down the slope, but instead she clenched the handlebars until her knuckles turned white and kept her eyes on the pathway ahead. She tried to push away the mental image of the blood-spattered cop and Jiri’s silent agony, but the scene was burned into her memory. A wave of nausea compressed her throat and stomach. I’m coming, Aunt Dita, she thought.

“It wasn’t civilized society anymore,” Ambrose continued. “It was chaos. The ESC Canopy Division Law was necessary because people were killing each other. It’s all archived. Look, I can show you footage of the press conference.” He held up his hand next to her face and flipped his palm.

Nothing happened.

She raised an eyebrow as he flipped it again. “What are you doing?”

“I can’t get online. No signal.”

“You use your hand for that?” She kept her eyes forward and hugged the wall as three ancient scoots sped past in the opposite direction, trailing pungent oil-based fumes.

“What do you mean? Everyone—” He paused, then started again. “It’s all embedded into the top of my spinal cord. Hardcoded receiver, transmitter, ID tags. I can externalize information through my palm. Up above it’s … not so strange.”

Mistletoe remembered that she had seen people palm-flipping in news footage. Externalizing. Big piles of information springing up out of hands and then disappearing into thin air just as quickly.

“Down here we need cells. And the signal’s always weak, if we can get one at all,” she explained.

“But it’s a free signal,” he said. “And it’s everywhere.”

She shrugged. “Up there, maybe.” They passed a row of mangy black dogs curled up next to the wall. The ones who were awake eyed them lazily, pink tongues lolling out the sides of their mouths. She felt Ambrose tighten his grip on her midsection.

“They probably won’t bite,” she said.

Ambrose swallowed. “So this wall with the broken windows is the side of an apartment building?”