"So." Stein straightened on the examination table with the focused energy of a man who had been waiting a long time for data. "What are the results?"
Jude looked at the readout in his hand, then at Stein, then back at the readout. "Surgery was a success. You're a girl now."
"What—"
"Don't listen to him." Caitlin stepped around Jude and physically moved him aside. "The results are complicated, but not catastrophically so." She took the report back from Wells, who had apparently helped himself to it while nobody was watching. "Body temperature is running at 39 degrees Celsius—we knew Ronnie ran warm, but not this warm."
"For Ronnie, that reading is probably equivalent to Flash's elevated metabolic baseline," Wells said, scrolling through the analysis on his tablet. "Subjectively normal. He's not registering it as a fever." He set the tablet down and moved to the main computer instead. "The more interesting finding is here. Professor Stein mentioned that he and Ronnie share each other's memories—which wasn't measured so much as reported, but it's completely consistent with what we're seeing at the atomic level."
"Which is?" Stein asked.
"The Firestorm Matrix is keeping both of you alive by using Ronnie's body as the physical host and your mind as the dominant consciousness. The body's survival instinct has found a functional equilibrium. But on the atomic level, Ronnie's body atoms are actively refusing to integrate with yours." Wells turned from the screen. "This isn't an immune response. It's not inflammation, it's not any standard biological defense mechanism. It's operating at an entirely different register—an atomic incompatibility that's generating heat as a byproduct." He paused to let that settle. "Heat that, if it continues to accumulate past a certain threshold, could trigger a chain reaction."
Shawna, who had been sitting quietly at the back of the room following approximately none of this, caught that last part. "A chain reaction?"
"A nuclear explosion, yes," Wells said calmly.
"What?!"
"Easy." Jude reached over and patted her shoulder. "First priority is to figure out Ronnie's yield. Get the numbers, then we can—"
"The first priority," Wells said, with the clipped patience of someone derailing a runaway train, "is separating Ronnie and Professor Stein's atoms before the rate of incompatibility reaches critical levels." He glanced between them. "The current split rate isn't alarming. It's been ten months since the accident, and the growth curve is relatively gradual. Provided Firestorm doesn't continue actively using his abilities, which accelerates the process, we have somewhere between one and two months."
"One to two months," Jude said helpfully. "Plenty of time to figure out an orderly evacuation route from downtown."
Professor Stein stared at him. The progression of emotions across his face—grief, fear, a flicker of genuine despair, and then a slow arrival at blank speechlessness—was really something to observe.
"Now," Stein said at last, "I understand exactly what Dr. Wells meant about your speaking style."
Caitlin appeared at Stein's elbow with a small paper cup. "Mood stabilizer and antipsychotic—it should help with the cognitive interference between you and Ronnie. We were going to include a sedative as well, but—" she glanced at Jude, "—apparently that's already been handled."
"I work efficiently," Jude said.
"Let's talk practically." Wells turned to Stein with the direct focus of someone who'd finished the pleasantries and was now in his actual element. "What's your assessment of your own situation? What do you need?"
Stein took the pills, swallowed them, and set the cup down. "I need to complete the Firestorm Matrix," he said. "It was my life's work—years of research, and the experiment had reached its final stage before the accident. The Matrix is what merged Ronnie and me together. But built into my original design was a decomposition function—the same fundamental process, run in reverse. If I can finish it, I may be able to separate us."
"In one to two months?" Wells asked.
Stein's jaw set. "The experiment was nearly complete. I believe it's achievable—especially with access to your resources."
Wells was quiet for a moment, turning something over in his mind. "Two additional thoughts," he said. "If the Matrix isn't completed in time, we'll need a contingency for the nuclear scenario—"
"Kill me."
Stein said it quietly and without drama. The room went dead still.
"I know what you're building toward, Wells. I've already thought it through. If the chain reaction becomes unavoidable, I'll end it myself before it can reach critical mass. Central City doesn't die because of me." He folded his hands in his lap. "What's the second point?"
Wells accepted that without argument. "Some time ago, I began developing a theoretical device—a fission apparatus I've been calling a quantum splicer. The concept is that it releases a concentrated burst of energy sufficient to replicate, at a controlled scale, the conditions of the particle accelerator. It would be enough to give the atoms in your body the force they need to separate cleanly."
Stein's eyes sharpened. "What's the fission element?"
"A tachyon. A faster-than-light particle." Wells folded his hands. "Mercury Labs had developed a prototype. Their tachyon device was stolen some weeks ago—I believe you're aware of that incident. If we want to pursue this option, we'd need to approach Dr. Christina McGee about developing a second prototype."
Stein was already shaking his head before Wells finished. "Christina and I know each other well enough that she'd understand immediately what I was asking for. The price of her cooperation would be access to the Firestorm Matrix project—a full research collaboration. That's not a trade I'm willing to make as a first option."
"Understandable." Wells looked regretful. "Then we focus on completing the Matrix directly. The lab will commit its full resources. In return, we'll need access to a portion of the project's technical documentation to contribute meaningfully."
Stein was quiet for a moment. Then, with a faint, dry edge: "I have Ronald's memories. I already know most of what goes on inside S.T.A.R. Labs. I'd say that's a fair exchange."
"I'd say the same."
The terms were agreed upon without ceremony. There was no contract, no handshake—just two scientists in a room who had decided, each for their own reasons, that the arrangement made sense.
That night, after the lab had gone quiet, Wells made his way to the back corridor alone. The wheels of his chair made no sound on the polished floor. He stopped at the concealed door, waited for it to recognize him, and rolled inside.
"Gideon. Show me the future."
The display materialized in the dim air—the familiar newspaper from 2024, its headline unchanged in the ways that mattered and changed in the ways that didn't. The Flash's byline was still absent, replaced by something new: a short column about a blazing object crossing the sky, described by witnesses as a meteor, leaving a trail of light visible across three counties.
Not a meteor, Wells thought. Firestorm, going critical. The butterfly effect, unfolding exactly as predicted.
He studied the headline for a long moment.
In the end, I'll have to step in.
The red light moved through his eyes like a dormant current.
"Barry," he said softly, to no one in particular. "You really are a lot of trouble."