Disclaimer: I don't own Supergirl or the characters. This is written purely for fun.

A/N: I started this a while ago, but have only recently found time to write it. It is dark and angsty, but there will be sister moments towards the end. This is set shortly after the S4 finale but doesn't really touch on Lena's reaction to Kara's identity.

"Here you go." Supergirl said handing an alien over to the DEO agents in the control room.

"Put him in containment." Alex ordered the agents who cautiously led the alien away.

"Have I said how good it is to be back?" Supergirl smiled at Alex.

"Just a few times." Alex smiled back.

"So do want a celebratory movie night?" Supergirl asked.

"I, uh," Alex started pulling a face.

"Have a hot date?" Supergirl guessed.

"Yeah. Sorry."

"Don't apologise. We'll catch up tomorrow for breakfast." Kara suggested. "Unless it's going to be a really hot date."

"Kara-" Alex started.

"I mean James told me all about Kelly's walk of shame this morning." Kara smiled.

"I'll see you in Noonan's tomorrow morning." Alex said.

"Okay. Anyway I should get back to CatCo. See you tomorrow. Have fun." Supergirl said before flying off.

"She seems happy." Brainy commented as he approached Alex.

"Yes she does." Alex agreed.

"Are you unwell?" Brainy asked.

"No. Why?"

"Your face is red." He pointed out.

"I'm fine." Alex said before changing topics and asking. "So what do we know about our latest prisoner?"

"There is nothing about his species in the DEO archives. I did not know his species had had contact with Earth before the twenty second century."

"Well clearly he has. So what do you know about him? And don't give me that timeline excuse."

"Protecting the timeline is not a mere excuse to annoy you." Brainy said.

"Good. So what do you know?" Alex asked.

-00-

As Supergirl flew across the city she saw smoke coming from a building. Changing course she flew towards the fire and used her freeze breath to put it out before entering the building looking for casualties.

"Hello." she called.

"Help!" A man called from a room.

"I'm coming." Supergirl said following the noise. As she entered the room she saw a man sitting on the far side of the room, knees pulled to his chest looking like he was frozen with fear.

"It's okay. The fire is out." Supergirl said as she approached him.

"Supergirl?" He asked looking up. "It's really you?"

"Yes. Are you hurt?" She asked.

"So hurt. The pain, I can't get over it."

"It's okay. I'm here to help." Supergirl said as she crouched by him. "Where are you hurt?" She asked as she noticed him clutching a box.

"So much darkness." He said.

"Can you see me?" Supergirl asked wondering if he was blind.

"Oh, I can see you." He assured her looking straight at her with wild eyes.

"Let's get you out of here." She said, feeling uneasy.

"Yes." He said opening the box. As soon as the lid was off Supergirl sagged back as dizziness hit. Looking down she saw a huge rock of green in the box.

"You will repent and you will pay." He said removing the rock and pressing it against Supergirl's chest, causing her to weaken further. As she tried to gather her strength he pulled a syringe from the box and stabbed the needle into Supergirl who screamed in pain before falling unconscious.

"Finally judgement will fall on you." He said.

-00-

As Supergirl woke up she was immediately aware of a familiar feeling of nausea, dizziness and general weakness. Forcing her eyes open she saw that she was wrapped in green chains. Using what little strength she had she forced her head up and found herself sitting in room that looked like a makeshift court. Only where the jury would sit were two benches lined with 12 puppets and dolls. At the front, wearing a black robe, was a further puppet that looked like a reject from the original Child's Play.

She then heard footsteps approach from behind as a voice she didn't recognise said.

"The defendant is awake we will begin."

"Who are you?" Supergirl asked as he moved in front of her.

"I am the prosecutor."

"Prosecutor?" Supergirl asked confused as she tried to focus on the figure, but he remained blurry.

"You have committed countless crimes against the people of this country. You will now be tried for each of those crimes and when found guilty you will be sentenced and punishment will be carried out immediately." He paused and then looked down at his book. "We will start with the first crime, environmental vandalism." Not giving her time to answer he approached the bench and said. "This court is in session. Supergirl you are accused of causing an oil spill in National City in October 2015. How do you plead?"

"Plead?" Supergirl asked, her brain not engaging.

"Yes plead. Did you cause and oil spill?"

"Yes." Supergirl said recalling the even from her early days.

"So you plead guilty?" He asked. "So noted. The judge will now pass sentence." He then looked at the puppet at the front and every so often nodded before commenting. "Harsh, but fair and fitting." He then turned to face Supergirl.

"You will stand for sentencing." He said.

Still dazed and confused Supergirl remained seated.

"I said you will stand for sentencing." He yelled before yanking her to her feet. He then calmed himself before saying.

"Supergirl you have been founded guilty to environmental damage. The punishment will be for you to have a toxic environment for thirty minutes." With that he picked up what looked like an oxygen cannister attached to a mask and walked back towards Supergirl.

"The contents of this cylinder has small traces of Kryptonite. Not enough to kill you as you breathe, but enough for you to learn what harming the environment can do."

With that he placed the mask on Kara's face and turned a valve forcing Kara to breathe in the poisonousness air.

TBC...

A/N: Thanks for reading and reviewing.