to investigate a discarded hamburger wrapper. Before that, he had squeezed beneath a fence around an abandoned house on Fletcher Road, where Eli found him barking at his own reflection in a broken window. Every time, his mother told Eli that the dog needed better training. Every time, Eli promised to work on it, and every time Rascal discovered a new opportunity to demonstrate that the lessons had not taken.
Eli's mother, Megan Mercer, worked scheduling shifts at the county medical clinic. She had come home shortly after four that afternoon carrying a grocery bag under one arm and a folder of paperwork beneath the other. Her cheeks were red from the cold, and she was tired in the particular way people become tired when they spend the entire day answering questions that should have been answered by someone else. She found Eli at the kitchen table with a pencil behind his ear, drawing a floor plan from memory on the back of an old worksheet.
"Homework?" she asked.
"Finished it," Eli said. "This is something else."
She put the groceries down and leaned over his shoulder. He had drawn the downstairs rooms of their house, including the back hallway and the narrow crawl space where the heating pipes passed beneath the kitchen. He had labeled the windows, the exits, and the places where the floor dipped slightly because the original foundation had settled. His mother studied it with an expression that mixed affection with the familiar uncertainty of raising a child whose interests had never aligned neatly with those of his classmates.
"You could draw normal things once in a while," she said. "Mountains. Basketball players. A dog that stays in the yard."
"I draw mountains," Eli replied. "But buildings have more interesting problems."
Megan smiled despite herself. "That sounds like your uncle Jonah."
Uncle Jonah Price repaired heating and ventilation systems for hospitals, schools, and industrial facilities across the county. He was Megan's older brother, a quiet man who treated an instruction manual with the respect other people reserved for a family Bible. When Eli was seven, Jonah had shown him how a school building could seem simple from the outside while hiding a complicated network of ducts, vents, corridors, and service shafts. He had given the boy an old flashlight, a compass, and a collection of discarded building diagrams, then taught him the most important rule of all: understanding how a system works does not give you permission to interfere with it when you do not know what is happening.
"You can be curious and careful at the same time," Jonah liked to say. "The smartest person on a job is the one who knows when to call somebody more qualified."
Eli remembered that part, though he would discover later that knowing when to ask for help could be more frightening than trying to solve a problem alone.