The Alchemy of Forever

collarbones creating dark hollows on my chest. I look sick. Weak. Still, my chapped lips curve into a smile. Dying is the bravest, most human thing I will have done in six centuries.
    After a hot shower, I dress in my favorite pair of faded green pants and a fuzzy hoodie and make my way to Cyrus’s library. It’s locked—none of us have ever dared enter here without his permission—but I know where he hides the key.
    The library is the one room in our home that is not sleek and modern. Floor to ceiling bookshelves line all the walls, holding a jumble of handmade bindings, sewn Coptic spines, and ancient leather-bound volumes. An Oriental carpet in red and turquoise stretches across the floor, a souvenir from the year we spent in Iran. The room smells like old paper, with a faint trace of Cyrus’s soap, notes of vetiver and cedar.
    This is his collection, a record of his hundreds of years of knowledge. As much as Cyrus appreciates human progress and technology, nothing can replace these weathered volumes. They have an almost talismanic power over him, which is why no one else is allowed in this room. We’ve taken the library with us every time we’ve moved to a new city. I cringe, remembering the trouble it caused on the voyage from Barbados to New Amsterdam. At least one person has died for these books.
    I run my fingers over the spines till I find what I’m looking for, and pull a slim book from the shelf. It has a lock closed over its front edge, like a diary. But I don’t need to read it to know what’s inside: the formula for making the elixir. Cyrus, the son of an alchemist, had learned how to make the elixir that unbinds the silver cord that anchors the soul to the body. He wears a vial of it around his neck at all times. It only takes a few drops to turn a mortal being into one of us: an Incarnate, a soul untethered from a specific body, who can live forever by stealing others’ lives. We only need the elixir once—then we can switch at will.
    Cyrus may have the formula memorized by now, but there’s a chance he doesn’t—after all, he hasn’t changed anyone into an Incarnate in almost a hundred years. That chance is enough for me.
    I sit at his desk and pull out a creamy sheet of stationery.
    Dear Cyrus,
    I loved you once, with all my heart, and I stayed alive, in one form or another, for centuries because I could not bear to be apart from you. But the years have changed us, and not for the better. Every death we’ve caused has killed our love, bit by bit. I cannot kill another human in order to live. When my current body is lost, I will be too.
    Until the next life, Seraphina
    Back in my room I fold the note and put it in the pocket of the dress I’ll wear tonight. Everything is in place. Doors open and doors close; I just have to walk through.
    By nightfall the fog is so thick that I can’t see more than twenty feet in front of me. The streetlights glow amber in the haze, reminding me of minerals in a fire. Cyrus once charmed me with colored fire instead of a bouquet of flowers, the pale powders in his palm giving little clue to the hue they brought to the flame. It seemed like magic, those little flames glowing red, glowing violet, the color of cat’s-eyes lapping at the dark. But it was only science—borax, copper chloride, potassium sulfate. I know that now.
    It’s just before ten PM when Charlotte and I arrive at Emerald City; the others have been at the club all day preparing. A large crowd of people is gathered outside the doors, bouncers holding them at bay while they check the guest list. Jared gives me an appreciative glance and parts the crowd for us to go inside.
    I shiver in my oyster-colored silk shift dress, a modern version of the one my real body died in so many years ago. I’ve always valued symmetry, and this feels like a fitting tribute to my original incarnation. A small car key is pinned to the underside of my bra strap, laying flat against my heart. I wear no jewelry except for my poison ring, the hidden compartment of which contains my parting gift for Cyrus.
    The second I step inside I’m overwhelmed by the thumping bass and loud voices. I walk slowly up the stairs, my heart pumping weakly. Charlotte places a steadying hand on my lower back.
    “Sera, you really shouldn’t wait this long to take a new body,” she whispers in a worried tone. “You’re pushing it.”
    “You know me,” I say with a forced laugh. “Always living on the edge.”
    Cyrus is