"Swap 'em," Ezra said quietly. "If it's the relay, the problem moves to the horn."
Julian's eyebrows went up a fraction of an inch. He didn't answer. He took a pair of relay pullers off his belt, plastic jaws worn smooth, and rocked the horn relay out of its socket, then the one in the third row, and changed their places, pressing each down with his thumb until it seated with a click you could feel more than hear.
"Brody," he said to the salesman. "Try it."
Mr. Kessler sighed. The women by the Porsche had drifted closer. The older one had her hands folded in front of her coat, watching Ezra, not the car.
Brody pressed the button.
The Bentley's engine came alive all at once, a deep, rolling bark that filled the showroom and rattled the bowl of green apples and settled into an idle so smooth it was more a feeling in the floor than a sound. Inside, the dash bloomed and held: a yellow parking-brake light, a tidy 1.0 mi on the odometer, a glowing P, and on the center screen a slowly rotating picture of a white Bentley, perfect, turning in its own little sky.
Nobody said anything for a second. The engine just kept going, steady, a big animal breathing.
"It started," Julian said. He sounded like a man who had walked into the wrong room of his own house.
Ezra let the corner of his mouth go up, just a little, just once. "I told you the battery was fine."
Mr. Kessler's arms were still crossed. But the smile was gone off his face like somebody had wiped a window, and for a moment, before he put something else there, he only looked old, and surprised, and caught.
II.
Julian Marek had been a Bentley-certified master technician for nine years, and for most of that time he had believed that the worst sound in the world was a customer saying it only does it sometimes.
Now he knew it was the sound of an eleven-year-old being right while you stood there holding the wrong part.
He let the car idle for two full minutes, watching the dash, waiting for it to falter. It didn't. He had Brody shut it down and restart it four times. Four clean starts. Then he plugged his scan tool into the port under the dash, the factory unit in its yellow rubber boot, and let it walk the modules while the engine ran. The stored codes were still there from the morning, a pile of them like leaves after a storm: low voltage in four modules, a communication fault with the engine controller, a starter-circuit implausibility. That last one was why he'd replaced the starter relay at nine a.m. It had made sense. It was the code that pointed loudest.