I walk over to Tris's table and stroke her hair, watching her face as I listen to her argue with Caleb on the screen.

She still shows no sign of what is going on inside her brain - her eyes are not moving behind the lids, her body is utterly still. I sigh and kiss her on the forehead. "Make Caleb explain himself," I whisper to her. "Don't go easy on him."

There's a special computer at Dauntless headquarters for encoding serum, and after a search around the lab, I find one. I crack my knuckles like a musician ready for a concert and sit down, tapping a key to wake the computer.

The system is password protected, of course. First, I try my Administrator's password for the Dauntless computer, but that doesn't work. Sometimes the easiest answer is actually the right one - usually after I've gone through all the tough ones, of course. Not this time, though.

I start going through all the hacking tricks I know. The screen tells me I will have 10 tries before I'm locked out, so I consider carefully and key in methodically. On the 8th try, I'm starting to sweat, when the computer accepts the password.

A sigh of relief is just escaping my lips when I hear Tris yell on the screen: "You could have tried, you coward!" Her face is flushed and there are tears in her eyes as she confronts her brother. "Tried and failed, because you love me!"

I watch her for a second, frowning. Interesting. She actually is making Caleb explain himself, and none too gently.

"Four!" Someone yells from down the hall. I jump up and open the door, looking out in the hall at Leo and Uriah dragging an unconscious Darius between them. Christina is limping behind them.

I help them get Darius in and lie him on the floor carefully.

"What happened?" I ask Leo, gripping Uriah's shoulder, grateful to see him alive and apparently unharmed. He grasps my arm in return. Leo keeps his eyes on Darius as Christina brings him the first aid kit. She crouches awkwardly next to him, wincing and sticking her leg out to the side.

"That nutcase, Edward," she explains when she sees me looking at her in concern. "Shot me in the leg." She smiles grimly. "But I got him back. Shot him, too, and poked him in the eye for good measure - his good eye." Uriah helps her treat her own wound while Leo looks Darius over.

"Where's Cara?" Leo suddenly says.

"She went to Jeanine's lab to get the Abnegation file."

"You sent her alone?" he growls, rising to face me.

"There wasn't much choice. I had to stay with Tris - and there's no time, is there? Are the Factionless in control of the building yet?"

Leo stares at me, giving the barest of nods.

I go to the surveillance screen to check on Cara. "There she is," I say nodding at the screen. She's standing in the open doorway to Jeanine's lab, arguing with someone.

It's Caleb Prior, and he has a gun pointed at Cara. Leo takes in the scene over my shoulder.

"Do you have any more weapons?" he asks quietly. I hand him the two guns tucked into my waistband. He throws one to Uriah, who catches it smoothly, rising to his feet.

"Take care of Darius for me," Leo says, heading for the door. "I've already lost one of my brothers today. I don't want to lose the last one I have." I look at Darius, startled, and realize for the first time that he has the same tight curls as Leo, the same stocky build.

Uriah hesitates before he moves to follow Leo. He walks over to the table and stares at Tris, taking her hand. "Come on, Tris," he whispers. "Come on, Divergent. You have to fight it." he puts her hand down gently. "You'll save her, won't you, Four?"

I nod, the muscles in my jaw tightly clenched. He nods back at me and runs after Leo.

Looking down at the surveillance screen, I wish Leo had stayed a little longer. Caleb just lowered the gun, shoulders sagging, and is following Cara into the lab.

"Do you need help?" I ask Christina, before returning to the encoding computer.

She shakes her head, "I have it," she says grimly, lifting Darius's shirt to reveal a crudely bandaged wound in his abdomen. "He's lost a lot of blood," she says. "But I don't think the bullet hit any major organs - doesn't seem to have internal bleeding. He was lucky. Go do what you have to do."

We both look up at the overhead screen as Tris shouts "Shut up!" Much to my shock, she is shoving Marcus into a wall. Christina makes a little gurgling sound of surprise, too. "I hate you, you know that!" Tris yells in his face. "I hate you for what you did to him, and I am not talking about Caleb." Warmth spreads through my chest, and I step closer to the screen. "And while I may not shoot you myself," she whispers to Marcus, "I will definitely not help you if someone tries to kill you, so you'd better hope to God we don't get into that situation."

I feel my eyes fill - I don't want Christina to see me cry, but I can't help myself. I keep my back to her as I walk to the metal table. "Thank you," I whisper to Tris, smoothing her hair back and kissing her on the forehead.

I wipe my face with the edge of my shirt and go back to the encoding computer to work.