"Barry!" Wells cried over the crackle of static coming from Barry's comm. "Barry, what happened out there?" No answer.
"Are you guys okay?" Cisco asked. Still nothing. In an instant, without any prompting, Kara had her suit on and was flying to Barry and Caitlin's last known location. She arrived in time to see Barry helping Caitlin up off the ground and speaking into his comm, probably- at last- answering Cisco's question. Kara touched down nearby, her landing sending up puffs of ash from beneath her feet, and looked around. Their immediate surroundings reminded her of nothing so much as what she'd always imagined Hiroshima and Nagasaki had looked like in the immediate aftermath of the nuclear detonations that had taken place there- burnt out and desolate, with flakes of ash drifting slowly through the air like snow.
"Oh God," Caitlin said suddenly. "The nuclear explosion. There's no telling how much radiation we were exposed to."
"Wait, wait, wait, this can't be," Kara heard Cisco say over the comm. "The Geiger counter in the suit- it's reading less than one millirad."
"But that's normal," Barry said, clearly puzzled.
"There's no radiation," Wells confirmed. At that, Barry turned to Caitlin and said, "Let's go," then scooped her up in his arms and raced off toward the place where they'd last seen Stein. Kara followed, arriving a few minutes after they did. They found a crater there, and Ronnie lying at the bottom of it. The only question that remained was whether he was himself again or whether he was still Stein.
"Did it work?" Cisco asked over the comm. "Did you separate them?"
"I don't know," Barry answered. Meanwhile, Caitlin was making her way carefully down the slope of the crater to Ronnie's side.
"Ronnie?" she asked, and Kara waited with bated breath at her brother's side to see what would happen next. Ronnie stirred as Caitlin approached him, and when he looked over at her, she said, "Tell me your name."
"Ronnie Raymond," Ronnie answered with a smile, and reached up to kiss her deeply. He pulled away long enough to murmur, "Cait, it's me," before kissing her again, and at that point, Kara had to look away, because she felt like she was intruding on something that was meant to be private.
"Um, pardon me," a voice said behind them, and they turned to see Martin Stein standing a short distance from the lip of the crater. Gesturing toward his ripped clothing, he added, "Obviously, I need a change of clothes."
"Nice to see you in the flesh again, Professor," Barry said with a smile, nodding to him. Stein returned the nod distractedly, seeming confused. Pressing a hand to the side of his head to activate his comm, Barry said, "We're coming home. All of us." and off they went.
Back at STAR Labs, Kara hung back to give the rest of the team space to have their reunion with Ronnie. She hadn't known him, and she once again felt like a voyeur or at the very least an intruder on a private moment. Eventually, she left STAR Labs altogether, figuring that they would call her if they needed her.
It was only once she'd reached the street outside that she realized that she didn't have a specific destination in mind as far as where to go now. The only thing that had been on her mind up to this point was getting out of STAR Labs. She wandered aimlessly through the streets of Central City for a while until she found herself at Jitters. By that time, it was sundown, and she was grateful that she'd never had to worry about getting mugged or assaulted.
Entering the building, she was surprised to see Ronnie and Caitlin, hunched over a table in the middle of what looked to be a pretty serious conversation. Either that, or an argument. It was hard to tell from where she was. Cursing the fact that she couldn't seem to stop accidentally butting into other people's private moments today, Kara was just about to leave when suddenly the red dots of laser sights appeared everywhere, and the patrons and staff of Jitters went down, tranq darts in their necks. Kara felt one strike her and bounce off, and she dropped to the ground, realizing that she should keep up the ruse that she'd been knocked out until these unknown attackers were gone and she could figure out what was going on and coming up with a strategy to deal with it.
When the loud bangs and screams and the hiss of gas canisters died down, Kara got up slowly from the floor to find everyone in the building unconscious and Ronnie and Caitlin gone. She could only hope that the lasster had gotten out when all of this had started. She ran out into the alley behind the building in time to see the STAR Labs van up and Caitlin open the door and shout "Get in!" and then Ronnie was hauling Barry up from the ground and shoving him into the van before jumping in himself and it was driving off before Kara had any time to react. At a loss, she leaped into the air and followed the van back to STAR Labs from the air, wondering what the hell had just happened.
A short time later, Kara stood in the Cortex, watching in horror as Caitlin pulled steel shards- like metal porcupine quills- out of Barry, wincing each time the latter yanked another one free and the former screamed in pain.
"I'm so stupid," Caitlin said angrily as she dropped a shard into the metal tray at Barry's beside. "Jason Rush- the grad student who was helping Professor Stein with his Firestorm research- he said that the Army took all of Professor Stein's material when he disappeared. I should have known it was General Eiling."
Damn it, Kara thought bitterly, realizing that she'd missed some critical information. She could only conclude that this General Eiling, whoever he was, had made a move on Ronnie, and that he was the one who had done this to Barry. She felt herself get heated with rage at the thought.
"Not your fault," Wells said, interrupting Kara's thoughts of vengeance. "He still thinks you hold the keys to the ultimate human weapon. Both of you."
"Okay, let's just finish this," Barry cut in in a pained voice. "I gotta get to Stein's house. Eiling's gonna be after him too."
"Stein's fine," Ronnie said suddenly.
"How do you know?" Cisco asked.
"He's right there," Ronnie replied, pointing. They all turned in the direction he had pointed and sure enough, there was Stein, standing in the doorway of the Cortex.
"I don't think Mr. Raymond and I are as distinctive as we'd hoped," he said dryly.
As soon as Caitlin had finished pulling the shards out of Barry, she took him, Ronnie, Cisco, and Stein into the treadmill room to confer with them while Wells went to go and talk to Eiling, hoping to find some way to negotiate with him and Kara stayed by herself in the Cortex. She just didn't think it was a good idea for her to be around other people right now. She wanted to hurt Eiling for hurting Barry, when she'd never before in her life wanted to hurt anyone. The thought, the sheer violence of it, scared her, and she needed time alone to get a handle on it.
The next thing she knew, the team was in a panic. Apparently, after they'd finished conferring and where all either out of the building or otherwise occupied, Eiling had kidnapped Stein.
"Where do you think Eiling took Professor Stein?" Caitlin asked when they regrouped in the Cortex to figure out what to do now.
"I imagine some off the books military research facility," Wells answered.
"We have to get him back," Barry said urgently.
"Easy," Wells cautioned. "Eiling has already demonstrated that he has the weaponry to disable the Flash, or worse. And for all we know, he might have some way of taking Supergirl off the board as well." At this, he locked eyes with Kara, who shifted uncomfortably under the scrutiny.
"Well, we can't just let him turn Stein into a weapon," Caitlin said.
"How do we find him?" Ronnie asked. When everyone turned to look at him, he added "What?"
They soon found out what- as it turned out, the connection between Ronnie and Stein was far from temporary, and the former quickly figured out how to use it to find the latter. Before long, he was heading with Kara and Barry to that location- an old decommissioned military research facility 300 miles away from STAR Labs- to rescue Stein. Together they stormed the building and managed to rescue Stein in the split second before Eiling was about to shoot him in the head. Faced with a military onslaught designed to prevent their escape, soldiers armed with weapons designed to stop them both- though, despite Wells' suspicions, Kara hadn't known that Eiling had even known about her until this very moment- the Allen siblings had no choice but to take a step back and watch as Ronnie and Stein used the quantum splicer to merge with each other once again in order to fight off Eiling and his forces.
"Home?" Barry asked when it was all over. Ronnie nodded, and off they went back to STAR Labs.
A few days later, the team went to see Ronnie and Stein off, as they had decided to leave Central City to find someone who could teach them more about their powers as well as stay one step ahead of Eiling, who was sure to come after them again once he managed to re-marshall his forces. As Kara watched them merge with each other once more and fly off, she knew that she hadn't seen the last of them. She looked forward to their next adventure together.