"Here's what I want you to understand," Malcolm said. "What Brent Caldwell thinks about what I can do, that has no bearing on what I can actually do?" "None. If I stood there and argued with him, what does that prove to him?" He's not looking for proof.

He's looking for a reaction. The argument isn't about competence. It's about his audience. So, you just don't care. I didn't say that.

Then what are you saying? Malcolm was quiet for a moment. I'm saying that knowing what you can do matters more than convincing strangers. He held her gaze. The work speaks, not us.

The work. Ava looked at him for a long moment, deciding something he could tell. She had her mother's habit of going very still right before she made up her mind. Then she said, "That sounds like something you tell yourself so you don't have to fight back." Malcolm blinked.

She turned and went back to her notebook. He stood there a moment longer alone with that and then went back to the generator. I was 40 minutes deep into the Henderson generator, had the injector timing circuit spread across the workbench, was correlating fuel pressure drops against RPM data he'd logged yesterday during a test run, and had actually started to forget about Brent Caldwell and the thin man with the wire- rimmed glasses and all of it when he heard the engines. Multiple engines, heavy, smooth, the particular sound of government vehicles that were new enough that they hadn't yet had any of the factory precision worn off them. He didn't look up right away.

He had a measurement to finish. Then then Ava said from somewhere near the garage door, "Dad." Something in her voice made him put down the caliper. Three black SUVs turning off the highway, passing the entrance to Titan performance motors without slowing. Brent Caldwell was standing in his lot, and Malcolm could see him watching as the vehicles continued past.

And there was something almost comical about the confusion on Caldwell's face. The slight lean forward, the I don't understand why they didn't tetop. The three SUVs slowed and stopped in front of Malcolm's garage, not in front at the way people stop when they've arrived at the exact destination they intended. Malcolm walked to the garage door and stood beside Ava. The driver's door of the first SUV opened.

A woman stepped out. She was maybe mid-40s, dark hair, pulled back, dressed in what Malcolm recognized as business practical rather than business formal. The clothes of someone who spent a lot of time in facilities where dress shoes were dangerous. She held a tablet computer secured with what looked like a hardened case. Behind her, two men in dark jackets got out of the second vehicle.

Not police, not military. Exactly. Something adjacent. One of them was already scanning the surrounding area in the automatic practiced way of someone whose job involved being aware of exits. The woman walked straight toward Malcolm.

No hesitation, no looking around to confirm she had the right place. The way people walk when they've been briefed. Malcolm Reed, she said. That's me of Reed Mechanical and Salvage. Yes.

She looked at him for a fraction of a second longer than the question required. And Malcolm understood she was doing what anyone did when a mental image they'd formed failed to line up exactly with reality. He was in work clothes. His hands were dirty. The garage behind him was organized the way a serious working mind organizes things, which is to say perfectly logical from the inside and chaotic looking from the outside.

I'm Dr. Rebecca Sloan, she said. Propulsion Reliability Director, Marshall Space Flight Center, Huntsville. She paused. Are you Dr.

Malcolm Reed? The word landed differently than Malcolm expected. He hadn't heard it spoken aloud addressed to him in his own garage in front of his own tools in 8 years, maybe longer. He'd stopped counting. He was aware of Ava going very still beside him.

I was, he said carefully. Your doctorate in aerospace propulsion engineering from Georgia Tech 2008 is on record. Your publications are on record. A technical paper on combustion resonance in reusable cryogenic upper stage systems published 2014 is on record. She held up the tablet.

I've been carrying this paper for 2 weeks. Dr. Reed, I need you to look at what we're looking at. Malcolm didn't move. Who sent you?

Marshall Space Flight Center in coordination with NASA headquarters and the Aremis program office. And why? He stopped himself. He knew why, but he needed a second. Dr.

Reed Rebecca Sloan said, and her voice dropped slightly, losing the official precision, becoming something more direct. I drove 3 hours from Huntsville, and I brought a security escort because what I'm about to show you cannot leave this conversation without clearance. We have a propulsion system for a lunar mission that is demonstrating an instability nobody on our team can account for. Two contractor teams have failed to isolate it. We have 18 days before the launch window closes.

3 weeks ago, someone on my team pulled your 2014 paper. She paused. It describes what we're seeing almost exactly. Malcolm looked at the tablet. Then he looked at Ava.

She was staring at him with an expression he had never seen on her face before. He looked back at Dr. Sloan. 18 days, he said. 17 and a half technically, as of this morning, across the road.

Brent Caldwell was standing at the edge of his lot. He'd been watching the whole thing. The men from inside his lobby had come out, too. They were all watching. Four men in polo shirts and pressed khakis standing across a two-lane Alabama road watching three government SUVs parked in front of Malcolm Reed's gravel lot garage.

Watching a woman in a NASA affiliated ID badge hand Malcolm Reed a secured tablet computer with the posture of someone who needed something badly and knew exactly who had it. Malcolm didn't look at them. He looked at the tablet. "Come inside," he said. Rebecca Sloan set up at the workbench.

Malcolm had cleared a section of it with two sweeps of his arm, setting aside the Henderson generator components with a care that was automatic, not dismissive, and she opened three windows of data on the tablet simultaneously. Propulsion telemetry, chamber pressure readings, thermal mapping of the cryogenic fuel delivery system. Malcolm stood looking at it with his arms crossed and said nothing for almost 4 minutes. Ava sat on a stool in the corner with her notebook open pencil in hand, watching everything. One of the men in dark jackets had positioned himself near the garage entrance, not blocking it.

Present. Walk me through what you've ruled out, Malcolm said. Rebecca pointed to the first data window. Structural resonance in the engine mount assembly ruled out after independent modal analysis. Turbo pump bearing degradation ruled out bearings were replaced and the signature recurred.

Software timing error in the control sequence ruled out by manual verification of the ignition controller code. Cryogenic propellant thermal state variance. We've logged its present, but two of our analysts say it's within acceptable parameters. What do your other analysts say? A small pause.

They're less certain. What does the instability look like? Pressure oscillation appears 11 seconds after each restart initiation grows not linearly. It accelerates. We've run 14 ground simulations.

In 11 of them, the oscillation grew to the point where automatic shutdown systems engaged. She tapped the screen. Three of them it damped out on its own. Nobody can tell me why those three behave differently. Did anything change between the stable runs and the unstable runs? ambient temperature, fuel load percentage, restart sequence timing was slightly different because the operators were human and the intervals weren't machine perfect.

Malcolm uncrossed his arms. His hand moved toward the screen and then stopped. "Old habit, you didn't touch secured hardware without being cleared." He looked at Rebecca. "May I?"