The needle slides into my arm for the seventh time today.

"Pheromone levels are stable." Dr. Vance withdraws the syringe and marks something on her tablet. "You'll need another injection in seventy-two hours. Miss one, and they'll smell human on you within the day."

I don't flinch. Haven't flinched since I was sixteen and they started the modifications.

"Understood."

Director Stone stands by the window of the medical bay, his reflection a ghost against the gray sky. He's been watching my final preparations all morning. Making sure his weapon is sharp.

"How are the fangs?" he asks.

I bare my teeth. The false canines extend on command, retract just as smoothly. Eight surgeries to get them right. The scars are invisible now.

"Functional."

"The contacts?"

I blink, and my green irises shift to something inhuman, amber with flecks of red. Vampire eyes. "Responding to adrenaline triggers as designed."

Stone nods. He hasn't smiled in the three hours I've been in this room, but something in his expression resembles satisfaction. "You've trained for this your entire life, Wren. Since the day we found you."

I remember that day. Nine years old, standing in the ashes of my childhood home. My parents' bodies already removed. Stone had appeared like a savior, his hand extended, his voice gentle.

The vampires did this. But we can stop them. You can stop them.

Sixteen years of training. Combat. Languages. Vampire history, customs, hierarchy. How to move like them. Speak like them. Be one of them without actually being one.

All for this mission.

"The target is Lucien Solaris," Stone continues, pulling up a holographic display. "Crown Prince of the House of Sol. Four hundred twelve years old. The Daywalker."

The image shows a male vampire in formal attire. Dark hair, a face built for severity, amber irises so vivid they seem to glow even in a photograph. He's standing in what appears to be sunlight.

I forget to swallow.

"He really can..."

"Walk in daylight. Yes." Stone enlarges the image. "A mutation that occurs once every thousand years in the Sol bloodline. It makes him the most powerful vampire alive. And the most dangerous."

I study the face of the creature I'm going to marry. The creature I'm going to kill.

"The House of Nyx has agreed to offer you as a peace bride. Your cover identity is Wren of House Nyx, a minor noble they're sacrificing to end the centuries-long war between houses." Stone circles the hologram. "You'll have access to the Solaris estate, to the prince himself. Your mission is simple: gain his trust, identify his vulnerabilities, eliminate the target."

Simple. As if assassinating an immortal who can walk in daylight is simple.

"Timeline?"

"One month maximum. Longer risks exposure." His pale eyes pin me where I stand. "The Order has invested significant resources in this operation, Wren. In you. Don't disappoint us."

I won't. I can't. The memory of my parents' bodies keeps me focused.

"I won't fail."

"Good." Stone deactivates the display. "The wedding is tonight. You'll be transported to neutral territory for the ceremony. After that, you belong to House Sol."

I stand, testing the way my body moves in its modifications. Everything feels almost normal. Almost human.

That's the cruelest part. I'm still human underneath all the alterations. Still breakable. Still mortal.

Going into a den of vampires with nothing but fake fangs and chemical camouflage.

"One more thing." Stone's voice stops me at the door. "The Daywalker is observant. Unnaturally so. He'll study you. Test you. Don't give him any reason to doubt."

"I won't."

"And Wren?" His expression softens slightly, the look he sometimes gives me, almost paternal. "When this is done, you'll have avenged your family. Everything they took from you."

I nod. Let the familiar hatred settle into my bones where it lives.

Vampires killed my parents. Vampires destroyed my life.

Tonight I marry one.

And within a month, I'll watch the most powerful vampire in existence die by my hand.

I walk out of the medical bay, my false fangs a weight against my gums, my doctored blood a lie in my veins.

The Daywalker won't see me coming.

No one ever does.