Peter heard his brother sigh; he knew Theo found Alicia overbearing at times. She should worry a little more, he had said to Peter on more than one occasion, and it was true: her confidence bordered on recklessness. Theo turned in his saddle, looking past Finn and Rey, who had offered only wordless indifference through the entire scene. This was Watcher business, who rode with whom. What did they care?

“That okay by you, Arlo?” Theo asked.

“Sure thing, cuz.”

“You know, Arlo,” Alicia said, her exuberant mood lighting up her voice, “I always wondered. Is it true that Hollis shaved his beard so Leigh could tell you apart?”

It was commonly known that as young men the two Wilson brothers had swapped girlfriends more than once, allegedly without anyone being the wiser.

Arlo gave a knowing smile. “You’d have to ask Leigh.”

The time for talk was over; they were running late as it was. Theo gave the order, but as they were approaching the gate, they heard a shout from behind:

“Hold up! Hold at the gate!”

Peter turned to see Michael Fisher jogging toward them. Michael was a First Engineer of Light and Power. Like Alicia, he was young for this job, just eighteen. But all the Fisher men had been engineers, and Michael had been trained by his father straight out of the Sanctuary. No one really understood what the engineers did—Light and Power was by far the most specialized of all the trades—beyond the fact that they kept the lights on, the batteries humming, the current coming up the mountain, a feat that seemed both as remarkable as magic and also completely ordinary. The lights, after all, came on, night after night.

“I’m glad I caught you.” He paused to catch his breath. “Where’s Maus? I thought she was riding with you.”

“Never you mind about it, Circuit,” Alicia called from behind. Her mount, a chestnut-colored mare named Omega, was pawing the dust, eager to ride. “Theo, can we please just go?”

A flicker of exasperation crossed Michael’s face. At such moments, his eyes pinching under his thatch of blond hair, his pale cheeks reddening, he managed to look even younger than he was. He said nothing but instead reached up to pass Theo the object he’d brought with him: a rectangle of green plastic with shining dots of metal decorating its surface.

“Okay,” Theo said, turning it in his hand to examine it, “I give up. What am I looking at?”

“It’s called a motherboard.”

“Hey,” Alicia called, “watch your language.”

Michael turned toward her. “You know, it wouldn’t kill you to pay a bit more attention to how we keep the lights on.”

Alicia shrugged. Her mutual antagonism with Michael was a matter of record; the two of them squabbled like squirrels. “You push a button, they come on. What’s to understand?”