The deer is still alive. A few months ago I didn't know what a deer was, suddenly it has become my favourite animal.

Matthew's lab is far more crowded than I was used to. Christina was there, of course, as well as Cara, Caleb, and someone I didn't know the name of but recognised as one of the doctor's that had been tending over Uriah. Zeke was noticeably absent but honestly he was the least of my concerns right now. There was only one thing of importance right now and that was Tris.

"This is evolutionary science, Matthew, you are all stepping on a very dangerous line," the doctor was saying. Adam, I think? I remember thinking that that wasn't a very professional sounding name when I was first told it.

I tune out most of his concerns although make note to reset his memories when this is over. I know the potential dangers of what we are doing and that is why all evidence of the life serum will be destroyed once its purpose is fulfilled. In the wrong hands it could be fatal. I notice a thin crease in Cara's forehead and assume she's thinking the same. For the first time in months I think of Will, how there is no body we can bring back, how hard seeing Tris wake up may be when she lost her brother. When Christina lost her boyfriend, I remind myself. I look to her and for the first time notice how close she seems to have grown closer to Matthew. She's sitting next to him, reassuringly rubbing his arm.

I grow impatient as Matthew and Adam discuss the logistics of the procedure, with Caleb, Cara, sometimes even Christina to my surprise, occasionally chipping in. It all blurs to me, whatever they are discussing is trivial and mostly irrelevant. I get off the stool I am perched on, interrupting whoever is talking, "we know how this is going to happen, can we please just get on with it." There, I managed to even say please.

I thought I came across as strong, determined, but the look the doctor gives me is one of pity. "Of course, Four, all this can wait for another day." He thinks that but he won't ever be given the chance.

We wait outside for what feels like hours as Adam and Matthew go about whatever they need to do to "prepare" Tris. I know this means extracting the bullets and tidying up the wounds so she doesn't wake and bleed out again, but I try not to think of it, I can't think of Tris like that again. Never again. Eventually Matthew comes out and I'm on my feet. I don't remember standing. "She's as ready as she will ever be, if you would like to come in we can administer the serum."

I nod. I'm about to follow him when I think of something, "Wait!" Matthew turns and looks at me waiting for me to continue, "Can we not do it in there, I don't want the first thing she sees is to be a laboratory."

He smiles at me, "Certainly, I don't know why I didn't think of it myself. We can set up a more natural hospital setting."

When I first saw Tris after returning to Chicago she looked asleep. As Matthew and Adam wheel her from the laboratory and towards my room, she looks cold, sick… beyond. My throat feels tight as I walk alongside the bed, gently touching the fingertips of her left hand. In the right there is a cannula, where it will be soon connected to the machine's that will help her return to me.

My makeshift room is the one where we stumbled into the night before we separated for our own missions and we slept on the couch together. I dragged one of the cots from the hotel in there initially, but now I push it to a side to make room for Tris. They put her bed against the wall and connect things to her that if I was Erudite I may have been able to name. But I was advised what they do- monitor her heart beat, blood pressure, respiration, brain waves and the bag of donor blood that is connected to the cannula in her hand by a long tube that will help restore the blood she lost.

"Four, we will need you to step back in order for us to treat her," Matthew says quietly next to me, I haven't let go of her hand. I hear him but I can't bring myself to move until Christina puts her hand over ours and I let go, letting her steer me back.

She looks so small in that bed surrounded by wires and machines. I watch as Matthew prepares a syringe with the life serum- it's the longest needle point I have ever seen. Before I even have time to wonder where they are going to inject her, he hands it to Adam who puts it straight into her chest- straight to her heart I realise. Matthew starts pumping her chest with his hands and Adam turns on the defibrillator. He's watching one of the screens, looking for a sign of life I assume. I watch as he charges it up and delivers a shock to her body, making it jolt. I feel as though my body jolt's with her only to rapidly deflate as I realise that nothing has changed. There is no activity on the screens.

Matthew continues compressions. "Is it working?" I manage to whisper.

Only Christina hears me but she responds, "Give it a minute, she's much bigger than a deer, the serum needs time to circulate."

I watch Adam shock her two more times, Matthew pressing so hard on her chest I worry he will break a rib. Time feels like it has slowed to a crawl, I watch a bead of sweat roll down Matthew's temple and I start to think it has failed. Tears start to well in my eyes, my chest feels tight, I can't breathe. I can't lose her. I can't.

Adam charges the defibrillator again and I close my eyes. I can't watch this fail, it is like losing her all over again. I feel someone hugging my arm and I turn towards it burying myself in whatever comfort I can get, wishing that it was her comfort. I feel defeated. I tried to fight for her and I've lost. The first tear starts to roll down my face.

And then I hear it, the largest gasp for air followed by coughing.