I try to keep my grunts to a minimum so Rodion doesn’t hear me. I wait until he’s all the way up before I start scaling the wobbly, rattling staircase. If he looks down and sees me, I’m fucked.

With each floor I ascend, my hands get more and more sweaty. The building has to be twenty stories high. I don’t like being way up here, not one bit. It was bad enough going up in the Ferris Wheel or the Skybox, but at least those were enclosed spaces. The railing of the fire escape barely comes up to my waist. I’m horribly aware how easy it would be to topple over the spindly metal edge.

I try not to look down as the pavement recedes below me. I try not to feel the breeze up here, or notice how close the clouds look overhead.

I peek up onto the roof, trying to see where Rodion went. After a moment, I spot him all the way over on the far side of the building, setting up some kind of tripod device.

My mouth goes dry as a desert as he pulls a sniper rifle out of his bag. Rodion plans to shoot Nero Gallo through his hospital window.

Wildly, I consider running back down the fire escape so I can find a phone to call someone: the police, or Sebastian. But I already know how useless that would be. Nero will be dead long before anyone can get here.

The only person who can help him is me.

I don’t even want to step up onto the roof. My whole body is screaming at me not to do it.

The roof is flat and open, with only a two-foot raised concrete ledge running around the perimeter. There’s no walls, no railing, nothing to stop me from tripping and falling off the edge. A couple of vent hoods poke up from the building below, but otherwise, there’s nothing up here.

Well . . . almost nothing. The building is old and in poor condition. In a couple of places, the perimeter is crumbling away. In the corner closest to me, I see a loose chunk of concrete about the size of a brick. I creep over to it, trying to move silently, my eyes fixed on Rodion as he sets the sniper rifle into place on its tripod.

I’m also trying not to startle the pigeons strutting around on the roof. Their cooing and fluttering helps disguise the noise of me creeping around. For that I’m grateful. But if I startle them into flight, Rodion is sure to turn around.

Quietly, I wriggle the chunk of concrete free. It’s hefty in my hands, but I wish it were bigger. Rodion is a beast. I’m only going to get one chance to take him down.

He’s laying prone on his belly now, peering through the sight of the rifle. He’s looking across the road, all the way over to the hospital. It’s too far away for me to see, but I can just picture Nero Gallo laying in his bed, pale and motionless. Maybe with Camille right beside him.

She might be holding his hand. Totally unaware that at any moment her lover’s head could disappear in a mist of blood.

I sneak closer and closer to Rodion’s massive frame. It’s the worst possible version of Red Light, Green Light. Any moment my shoe could crunch a pebble or a bit of broken glass, and Rodion could turn.

Luckily he’s immersed in adjusting his barrel, checking the sight again, and curling his finger around the trigger.

I’m so close that I can smell the stale scent of cigarettes on his clothing, and his hateful cologne. I grip the concrete tightly in both hands, raising it up, readying to bring it smashing down on the back of his skull.

At that moment, one of the pigeons takes off from the roof with a percussive explosion of wings. Maybe something scared it. Maybe it just wanted to see me dead.

Rodion’s head whips around. He fixes me with his puffy, bloodshot glare. I try to smash his head regardless, but he rolls away from me, and the concrete only hits him a glancing blow on the shoulder. Not even close to enough to disable him. Meanwhile, I’m off-balance from the force of my swing.

I stumble, trying to snatch up the sniper rifle instead. Thinking maybe I can shoot him at close range. The weapon is heavier than I expected, bulky and awkward. Rodion has jumped to his feet. He easily wrenches it out of my hands, yanking so hard that he almost breaks my fingers.

Instead of turning the gun on me, he tosses it aside. His mouth is slightly open, showing the dark emptiness within. He isn’t making any sound, but from the shape of his lips, it almost looks like he’s laughing.

He circles around me, half-crouched, daring me to make a move.

I know I’m doomed. Rodion is bigger than me, and stronger. He knows how to fight—I don’t. He feints at me. When I stumble backward, trying to get away from him, his mouth opens again and he makes a quiet huffing sound that I’m certain is his version of laughter.

His dark eyes are gleaming, and his round, ugly face is red from the sun and the exertion of climbing up here. He holds up one big, scarred hand, beckoning to me, daring me to attack him.

Instead, I dive for the dropped piece of concrete and snatch it up. I throw it at him as hard as I can, trying to smash his teeth out. He bats it away easily, then charges at me.

I manage to slip his arms by an inch, but he grabs hold of my ponytail and yanks me back. I hit him in the face as hard as I can. It’s like punching a sack of sand. He barely seems to register the blow. Instead, his piggy eyes gleaming, he pulls one fist back and pops me in the shoulder, right where I was shot.

He didn’t even hit me full force, but the pain is explosive, blinding. I crumple to the ground, gasping, my right hand clamped over the spot that has become a flaming ball of agony. I felt the stitches tear, and I’m sure I’m bleeding again.

Rodion seizes me by the throat and hauls me upright again. He’s lifting me off my feet, Aida’s too-small sneakers dangling while I kick helplessly. Rodion starts to carry me toward the ledge.

It’s my worst nightmare: he’s going to fling me off the roof and there’s nothing I can do to stop him. I’ll feel his hands release, I’ll feel myself floating weightless through the air, then rushing with sickening force toward the unforgiving concrete.

Maybe this is why I’ve always been so afraid of heights.

Some part of my brain looked into the future, and saw that this is how I die.

I’m clawing at his arms, kicking and squirming, but his hand is locked around my throat. Already my vision is blurring, my head getting dizzy and light.

I look into his cold, dead eyes and I wonder if there’s anything I could do to make him stop.

I stop scratching his arms. Instead, I bring my right hand up to my face. I raise my first two fingers and touch them to my forehead in a motion almost like a salute.

It’s one of Rodion’s signs—the one he uses to refer to my father.

I’ve never used his signs before. Never even admitted that I knew them.

I can see the surprise in his eyes.

He hesitates, and I do the sign again, as if I have a message for him. A message from my father.

He lowers me down slowly, relaxing his grip on my throat so I can speak.

“My father says . . .” I croak, and then I give a fake little cough, stalling for time.

The moment my feet touch the ground, I lunge forward and reach around his back. My hands close around the handle of the Beretta tucked in the waistband of his pants. I yank it free and throw myself backward, as Rodion’s fist comes swinging around an inch in front of my nose.

I thumb the safety and point the gun right at his chest. I shoot him three times in rapid succession, the bullet holes disappearing in the featureless expanse of his black t-shirt.