The workshop was quiet, save for the hum of the servers and the rhythmic clack-clack of a Newton's cradle on the desk.

  Tony was sitting on the floor, surrounded by empty boxes of takeout and stacks of old Stark Industries blueprints. He looked terrible. His skin was grey, sweat beaded on his forehead, and the black veins on his neck were throbbing.

  He wasn't looking at the blueprints for the Expo. He was staring at a hologram floating in the middle of the room. It was a loop of the party. Specifically, the moment fight froze.

  I walked down the glass ramp. "You look like hell, Tony."

  Tony mumbled something, not looking up. He swiped the hologram, expanding a graph full of static.

  "Explain this," Tony said, pointing at the jagged red line.

  I set a fresh coffee on the workbench. "It's a graph."

  "It's a void," Tony corrected, his voice raspy. "I checked the suit logs. JARVIS ran a full diagnostic on that moment. You know what he found? Nothing."

  He looked up at me, his eyes bloodshot and confused.

  "No magnetic field. No heat source. Just... weight. The hydraulic pressure in the Mark IV legs spiked to critical, like the air suddenly weighed five tons. But the sensors? Blank."

  He tried to stand up, stumbled, and had to grab the desk to stay upright. He breathed heavily, glaring at me with the frustration of a man who couldn't solve the equation.

  "I don't like blank variables, Adrian," Tony spat out. "I don't like things I can't measure. Is it tech? Mutation? Because if you have a weapon that can shut down my suit without triggering a single sensor, that's a problem."

  "It wasn't a weapon," I said calmly.

  I took a sip of my own drink, keeping my posture relaxed. "I stopped you from killing your best friend. I stopped you from leveling your own house. If I wanted to hurt you, I wouldn't be bringing you coffee."

  Tony stared at me. He ran the logic. He hated it, but he couldn't argue with it. He slumped back against the desk, the fight draining out of him.

  "Fine," Tony muttered, rubbing his temples. "Fine. You're a scary, invisible variable. We'll table that. I'll figure it out later. Right now, I have bigger problems."

  Ensure your favorite authors get the support they deserve. Read this novel on Royal Road.

  He tapped the Arc Reactor in his chest. "I'm at eighty-nine percent toxicity. My mouth tastes like a penny. I'm dead by Friday."

  He kicked a box of old tapes across the floor. "And Fury thinks the answer is in this junk. My dad's old home movies."

  "Have you watched them?" I asked.

  "I'm not in the mood for a lecture from the grave, Adrian."

  "Watch it," I said. I walked over and threaded the film into the projector myself. "Humor me."

  Tony rolled his eyes, but he didn't stop me. The film flickered to the wall. Howard Stark, young and sharp, standing in front of the 1974 Expo model.

  "I'm limited by the technology of my time," Howard said on screen.

  "See?" Tony gestured vaguely at the wall. "He's selling tickets. It's a pitch."

  "He's not selling," I said. "He's confessing."

  I walked over to the physical model of the Expo that was taking up half the floor space. "Howard was paranoid, Tony. He didn't trust the government, and he didn't trust the board. If he found a new element, he wouldn't write the formula down."

  "Why not?"

  "Because they'd turn it into a bomb," I said. "He hid it where only you would look."

  Tony looked at the screen, then at me. He pushed himself off the desk, limping slightly as he walked over to the model. He looked down at the plastic trees and the Unisphere.

  "It's just a model, Adrian," Tony sighed. "It's not a treasure map."

  "Stop looking at it like a fan," I said softly. "Look at it like an engineer. Look at the negative space."

  Tony frowned. He leaned in. He traced the line of the main pavilion. Then the walkways.

  "The spacing is wrong," Tony murmured. It wasn't a realization; it was a criticism. "You can't funnel foot traffic like that. It's too rigid. It's..."

  He stopped. He tilted his head.

  "It's not for people," Tony whispered.

  He grabbed the frame of the model. "Jarvis, scan the board. Digital copy."

  "Processing, sir."

  "Drop the fluff," Tony ordered, his hands moving in the air, manipulating the light. "Get rid of the landscaping, the exits, the parking lots. I just want the structure."

  The hologram formed into the air. The Expo vanished, leaving only a glowing blue wireframe.

  Tony stepped back. The cynicism was gone.

  "That magnificent son of a bitch," Tony breathed.

  He spun the sphere.

  "Protons, neutrons," Tony pointed, his finger tracing the pavilions. "The walkways are the electron bonds. It's not a theme park. It's an atom."

  He looked at me, eyes wide. "He synthesized it. He actually found a replacement for palladium."

  "He built the engine," I said. "He just needed someone to turn the key."

  Tony looked at the frozen image of his father on the wall. "My greatest creation... is you."

  For a second, Tony looked like a kid. Just for a second. Then, he blinked, and the mask came back down.

  "Okay," Tony said, his voice hard and fast. "Okay, we're doing this. I need to synthesize a heavy element. In a basement. Easy."

  He looked around the room.

  "I need a prism," Tony said, snapping his fingers. "And I need to tear up the floor. We need to lay pipe for a particle accelerator."

  "I'll get the sledgehammer," I said.

  "Get the big one," Tony grinned. It was a manic, desperate grin, but for the first time in weeks, he looked alive. "We're gonna make a mess."

  I walked to the tool wall and tossed him the heavy sledgehammer. He caught it, testing the weight.

  "Hey, Adrian," Tony said.

  "Yeah?"

  "The gravity thing?" Tony pointed the hammer at me. "If I live through this? I'm going to figure out how you did it."

  "Good luck, Stark," I said.

  Tony swung the hammer. CRACK.

  The concrete shattered. The work had begun.