Laverty leans down for a close look, hands on his knees. “Hard to tell,” he says. “Either a 2 or a Z.”

BRADY

“My boy is a genius,” Deborah Hartsfield used to tell her friends. To which she would add, with a winning smile: “It’s not bragging if it’s the truth.”

This was before she started drinking heavily, when she still had friends. Once she’d had another son, Frankie, but Frankie was no genius. Frankie was brain-damaged. One evening when he was four years old, he fell down the cellar stairs and died of a broken neck. That was the story Deborah and Brady told, anyway. The truth was a little different. A little more complex.

Brady loved to invent things, and one day he’d invent something that would make the two of them rich, would put them on that famous street called Easy. Deborah was sure of it, and told him so often. Brady believed it.

He managed just Bs and Cs in most of his courses, but in Computer Science I and II he was a straight-A star. By the time he graduated from North Side High, the Hartsfield house was equipped with all sorts of gadgets, some of them—like the blue boxes by which Brady stole cable TV from Midwest Vision—highly illegal. He had a workroom in the basement where Deborah rarely ventured, and it was there that he did his inventing.

Little by little, doubt crept in. And resentment, doubt’s fraternal twin. No matter how inspired his creations were, none were moneymakers. There were guys in California—Steve Jobs, for instance—who made incredible fortunes and changed the world just tinkering in their garages, but the things Brady came up with never quite made the grade.

His design for the Rolla, for instance. It was to be a computer-­powered vacuum cleaner that would run by itself, turning on gimbals and starting in a new direction each time it met an obstacle. That looked like a sure winner until Brady spotted a Roomba vacuum cleaner in a fancy-shmancy appliance store on Lacemaker Lane. Someone had beaten him to the punch. The phrase a day late and a dollar short occurred to him. He pushed it away, but sometimes at night when he couldn’t sleep, or when he was coming down with one of his migraines, it recurred.

Yet two of his inventions—and minor ones at that—made the slaughter at City Center possible. They were modified TV remotes he called Thing One and Thing Two. Thing One could change traffic signals from red to green, or vice-versa. Thing Two was more sophisticated. It could capture and store signals sent from automobile key fobs, allowing Brady to unlock those vehicles after their clueless owners had departed. At first he used Thing Two as a burglary tool, opening cars and tossing them for cash or other valuables. Then, as the idea of driving a big car into a crowd of people took vague shape in his mind (along with fantasies of assassinating the President or maybe a hot shit movie star), he used Thing Two on Mrs. Olivia Trelawney’s Mercedes, and discovered she kept a spare key in her glove compartment.