(I really wanted this to happen before I actually watched episode. I did enjoy 2x07, but I just think it would've been interesting.)
Mon-El was already gone for a 2 months and a half before Kara found him in Cadmus' lair, in a room full of medical equipment. She found him a week after Cadmus took her blood and Jeremiah helped her escape. She went back to find Mon-El laying down on a metal, surgical table. She stared at his stubble that had grown over time, along with his messy hair. This image of him reminded her of when he was in the DEO while he was still asleep after his landed on Earth from Daxam.
"What did they do to you?" Kara asked him without expecting an answer. She reached her hand out for his shoulder, but before she could, Mon-El opened his eyes and he sprung up. Like the first time he woke up, he was going to grab Kara's throat, but Kara grabbed his wrist first and twisted his arm. Mon-El grunted in pain, but he used his other hand to slam her head on the table.
"Mon-El," she groaned, "what are you doing?"
Kara stood up straight to see Mon-El, but he was no longer on the table. She turned around to find him, but ended up being tackled on the table, breaking it. Mon-El was stronger than before, Kara noticed that, yet she was still powerful. Before Mon-El could punch her, she caught his fist, squeezing and twisting it. She kneed him in the groin and kicked him off of her, sending him in the air. But Kara didn't expect Mon-El to stay in the air rather than hitting the wall behind him.
Oh, Rao, he can fly, Kara thought. Mon-El tilted his head, staring at her with no remorse for his actions. His face was cold, not empathetic, but empty like he wasn't himself.
"How can you-"
"Fly?" Mon-El landed on his feet. He ripped off the metal leg of another table as he began walking to Kara. She stumbled a little before getting up. "Cadmus helped me. They enhanced my powers with guess what?"
Kara took a few steps back from Mon-El when he began to get closer.
"Your blood. Well, your DNA in your blood cells." He glared. "You know, I saw you hear last week, and you left me here to be tortured. I saw you escape. You betrayed me to save yourself."
Kara stood still, refusing to show any fear. But she wasn't scared of him, she was scared of hurting him. "No, Mon-El, I lost my powers so they could take my blood because they said they would kill you. They know your weakness is lead. I couldn't let you die. I was gonna back for you."
The area around Mon-El's eyes turned bright orange and showed his veins. He had heat vision. As soon as Kara figured out what he was going to do, the two both used their heat vision against each in sync.
"Why are you doing this?" Kara yelled at him.
Before Mon-El could respond or do anything else, he turned off his heat vision, and before Kara could harm him or anything else, she turned hers off, too. He touched the back of his neck and felt a dart in it. He looked back up at Kara with soft eyes then fell to the cold floor. Kara looked at his knocked out body and up to see J'onn with a gun.
"Liquified lead in dart guns. Not enough to hurt him, but enough to knock him out for a while." He told her. Other agents behind him, including Alex, came in the room.
"What happened?" Alex asked Kara, putting her weapon down.
Kara sighed. "Mon-El shares my powers."
Alex furrowed her brows. "What? How? What did he do?"
"He tried to kill me." Kara added. Alex frowned and looked at J'onn when he went up to them. "H-He said that I betrayed him. He looked so angry."
Later, they all went back to headquarters, trying to figure out what was wrong with Mon-El. They even locked him in his old cell that they put him after attempting to send a message to Daxam. He was locked in a seat that restrained him with lead to reduce his strength.
"Maybe when Cadmus enhanced his powers by combining your DNA with his, it enhanced his emotions-his anger." Alex suggested to Kara.
The two looked at the screen of the DEO's computer. They took a sample of his blood and ran it through to see his cells by cutting him with a knife made of lead.
Kara shook her head. "No, I don't think it works that way. And when I tried to explain to him what really happened last week, he didn't care. He wasn't himself, I know he wasn't."
Alex put her hands on her hips and observed his half-Kryptonian-half-Daxamite DNA. "So, in a way it wasn't really an enhancement." Kara looked away from the screen and looked at her sister. "He has new powers now, which were originally yours. An enhancement would've just built his strength and possibly increase his chances of flying. He can leap really high, that's for sure. Well, he did. And he's still weakened by lead and immuned by Kryptonite."
"Maybe they brainwashed him." Winn suddenly appeared by them. Kara flinched in shock. Winn giggled and took out a french fry from the little french fry box.
Alex looked at Winn. "Brainwashed?"
Winn nodded. "Yeah. You guys are too busy thinking his DNA is connected to his emotions and feelings towards Kara."
Alex agreed. "So maybe before or after they altered his DNA, they brainwashed him into wanting to kill Kara. Like how Maxwell Lord brainwashed Bizarro into wanting to kill her. Bizarro had Kara's DNA, too, so-"
"There could be a way to stop and help him." Kara finished for Alex.
"Supergirl," an agent went to her, "Mon-El's beginning to wake up."
Kara looked at Winn and Alex, giving them a nod. "Let's go."
The sisters left Winn to go to Mon-El. "O-Okay. I'll just wait here then." he said. "Alone. Now I'm talking to myself. I'm still talking to myself-stop it!"
Mon-El was fully awake when he saw Alex and Kara in front of his cell.
"Supergirl, the damsel who thinks she can save people from distress, you're here." Mon-El smirked. "Are you going to kill me?"
She shook her head. "No. Why would you even think-" she stopped herself from talking. She knew exactly why he was acting this way.
"Mon-El, you were brainwashed." Alex told him. "They've changed you. Who you think you are right now isn't you. You don't want to hurt Supergirl."
Mon-El scoffed. "Cadmus didn't change me. They showed me the truth and made me realize who the real enemy was." He looked at Kara. "You. You're a monster."
"Cadmus thinks aliens are monsters, you don't. If I'm a monster, then what are you? You're pretty much an alien-hybrid now. Cadmus gave you new powers; my powers. They were going to kill you. And now they're using you." Kara said.
"These powers are mine now, you don't own them. I feel stronger now, but you're using lead to hold me back. You're just jealous that I'm like you and Superman now. Two Kryptonian heroes intimidated by a Daxamite-a Daxamite who now has your DNA and your powers." Mon-El laughed. "And Cadmus isn't using me. I want to hurt you. Every bone in my body wants to rip you apart the same way you're ripping apart this planet."
Kara stared at this "new" Mon-El. The way he spoke seemed so convincing. But she knew better.
"Don't let him get to you." Alex whispered to her.
"You two do know your restraints aren't going to stop my super-hearing, right?" He commented.
Kara sighed. "I'm not gonna stop helping you."
They left Mon-El alone again while he rambled on how his restraints were too tight.
"If Cadmus is capable of brainwashing Mon-El, we can set him back to his original state. Clearly, they somehow altered his memories of you or wiped good things about you." Alex told her. "His powers, we can't take away. Not that that's necessarily a bad thing. We just have to make sure he doesn't hurt anyone, including you, Supergirl." Alex rubbed her shoulder.
Kara looked down. "Maxwell Lord used electroshock "therapy" on Bizarro to brainwash her. I'm not letting anyone hurt Mon-El the way Maxwell did her."
Her sister sighed. "Kara-"
"Alex, the pain we'd have to put him in won't affect him the same way as Bizarro. Bizarro could barely speak. Her cerebral cortex was barely functioning." Kara cut her off. "What could happen with Mon-El?"
"He'll heal and recover quickly. He's strong…-er" Alex answered. "The pain will, yes, is intensified, but-"
"Electroshocking someone is wrong, Alex." Kara shook her head.
"Cadmus probably used it to get him into hating you. We're just undoing the problem."
"We're undoing the problem with another problem."
"Well, if we don't, we'll continue having him as a problem. Do you really want to have Mon-El has an enemy?"
Kara sighed, shaking her head. "No," she mumbled.
Later, the agents got Mon-El and restrained him somewhere else where they were going to start the electroshock therapy. They put the brainwashing helmet on him and injected him with enough lead to weaken him and make him more vulnerable to the "treatment".
"What are you-Kara, what are they doing?" Mon-El tried to pull against his restraints.
"We're undoing what they did to you." Kara kneeled in front of him. "I'm really sorry."
Mon-El shook his head. "Please, don't let them do this to me!"
Alex glared at him. "Just an hour ago you were saying how you wanted to kill Supergirl and now you want her help?"
Kara stared at Mon-El with a sad look. "I'm so sorry, Mon-El."
Mon-El's sad face turned cold. "Monster." He called her.
Kara kept a still face. She stood up and the agents looked at Alex for permission on when to stop. Alex looked at Kara, but she walked out the room. Alex looked back at the agents and nodded.
The room was quickly filled with Mon-El's screams. The shock hurt him way more than Bizarro. Bizarro didn't have much to change besides what she felt for Supergirl. Her brain wasn't a proper functioning brain.
Mon-El tried to cry out for them to stop, but couldn't with the mouth guard that was forced in his mouth before they began electrifying his brain. Kara heard it and blocked her ears with her fingers. She walked away from the door of the room where Mon-El was. This was one of the times she didn't want super hearing.
"Where are you going?"J'onn asked.
Kara frowned. "I can't hear or see this. I just… I need to go. Let me know when this is done."
J'onn nodded, understanding.
Kara left. She decided to fly over National City. She needed to clear her mind. Thinking of Mon-El was too distracting and painful. What Cadmus did to him and what the DEO was doing now was terrible. When Mon-El wanted her to tell them to stop and when he yelled in pain. She wanted to help and tell the agents to stop what they were doing, but she knew Cadmus got too deep in his brain that finding another way to help him was useless. There were no other options.
No other options. No other options. Kara continually thought this until she figured out how wrong it was. Deep down, Bizarro had good in her. She regretted what she did to Kara, and she was never truly evil, even if Maxwell used electroshock therapy on her. Maybe if they had wait for Mon-El to realize that Supergirl wasn't a threat or if there was some kind of trigger to bring in memories of Kara that showed she was a good person and a hero, he wouldn't have had to go through electroshock therapy again.
"Oh, no." Kara said and flew as fast as she could back to headquarters. She raced to the room Mon-El was in and saw his head hanging down, his eyes closed. Sweat streamed down his head and his body twitched. The therapy stopped and Kara thought why.
Alex gently took her hand. "It's done."
Kara took her hand out of her sister's and went to Mon-El to take the helmet off and his mouth guard.
"Hey, hey, hey." Kara lifted his head to face her. He was groggy. "Mon-El, I'm here, I'm here. It's okay." She caressed her hand on the side of face. "I'm sorry. I'm so sorry."
A day later, Mon-El woke up on the same bed he was in when he first arrived to Earth. He was still restrained with lead in case the electroshocking didn't work.
His eyes opened slowly, seeing Kara and Alex.
"Mon-El," Kara whispered, sitting on his bed. Mon-El furrowed his brows. He looked around the room then back at Kara.
"What's wrong?" Kara asked him and Alex. Did they accidently wipe all his memories?, she thought.
He looked at Alex and he smiled very slowly. "You know, you look a lot like a doctor from a show I watch." He said softly. His voice was weak, but the sisters could still hear him.
Kara and Alex looked at each other and softly laughed, then looked back at Mon-El.
"I'm hungry." He groaned. He wanted to sit up and stretch, but his wrists were restrained, including his legs. "Oh."
"We had to restrain you." Alex said. Mon-El nodded, then looked at Kara. "I'll leave you two alone."
"If you're gonna ask me to take off the restraints-"
"I wasn't. But my chins a little itchy, so…" Mon-El smirked. Kara smiled. "I really like your smile." He said, unable to hold his compliment.
Kara looked down, hiding her blush.
"No, don't look away." He chuckled. Kara looked back at him. His smile faded. "I'm really, really sorry, Kara. What I did-I don't know. I don't know how to say sorry."
She shook her head. "No, Mon-El. That was Cadmus talking, not you."
"Yeah, but I… When they did that to me, I felt like I was in control. Everything I said and did, it felt like I wanted to say it." Mon-El said.
"But you didn't. Did you?"
Mon-El shook his head. "Of course not. I mean, I can't really remember what I did and said, but I know it was awful. I hurt you-"
Kara grinned. "I have super strength, I can handle your punches." Mon-El looked at the ceiling and giggled. "But can you handle your new abilities? I mean, you have my powers now. You have Daxamite and Kryptonian DNA."
"Well, thanks to your DNA, the headache I'm feeling right now probably isn't as bad as it would've been if I didn't have it." He said back at her. "Thank you though."
"For what?" She asked.
"For not giving up at me." He answered. "You stayed. After everything I did, you stayed, and I can't think of any way to repay you."
Kara thought about the way they brought him back. She sighed. "They… we hurt you. You're restrained with lead."
"Shh, I know what happened. I'd rather not relive it." Mon-El closed his eyes. "I'm gonna sleep."
"Yeah, of course."
Mon-El's hand - even though his wrist was restrained - grabbed Kara's hand before she could live. "Can you just…" Mon-El yawned, "stay with me, please."
Kara nodded and sat back down. She rubbed his hand with her thumb and used her other hand to brush his hair out of his face. His hair wasn't very long, but it grew during the time Cadmus had him. She stared at him fall asleep and move around a little bit, despite being trapped to the bed.
Even after everything, he looked like a little boy from Daxam who was just tired. And she was just a scared little girl from Krypton.