To my first readers and friends: Patti Rossier, Lauren Charles, Ashley Hartzell, and Ley Saulnier. You are some of the most beautiful, insightful, brilliant people I have ever met, and I’m honored to know you. Ashley, you saved me, girl, and I love you.

To the YA Scream Queens—Courtney Alameda, Jenn Johansson, Lindsay Currie, Trisha Leaver, Hillary Monahan, Lauren Roy, Cat Scully, and Sarah Jude Bromley—for showing me that there is a place for me and my weird brain, and for bringing YA horror to ready and willing readers (including me!). You are queens of the highest order.

A gigantic thank-you to the illimitable Kat Ellis, for the cake, coffee, and chats. I cherish them more than I can say! To my agent sister, Jen Rose Bell, for your enthusiasm, support, and beautiful spirit—I am so glad Polly brought us together! To Neil Jackson, Sarwat Chadda, Tara Kemsley, and Lia Keyes—thank you for the writing retreats! Here’s to so many more.

To my friends, who keep me grounded and happy: my twin and forever chop, Stacey Poulton; my beautiful and kind Mandip Kaur; my Mrs. Moose, Yurena Diaz; the wonderful and cherished Kimia Ahmadi; the lovely Colleen Mulhall; and my personal Viking, James Lidgey-Hutt. To anyone I haven’t mentioned, forgive a frazzled writer—but I love you, I do!

A big thank-you to my beautiful model, Amy! You are a perfect Kaitlyn and just gorgeous!

And you. If you’re reading this book, thank you so much. Words can’t express the honor I feel, knowing that you went on this journey with Kaitlyn too. Thank you.

AUTHOR’S NOTE

The Scottish Mala and Grundi aspects of this book are fictional, inspired by a childhood of travel and exposure to various cultural, tribal, and religious beliefs. Additionally, the fictional “Fair Island” in the book shouldn’t be confused with Fair Isle, which is a very real, very beautiful island off the coast of Scotland and part of Shetland.

Dissociative identity disorder is a fascinating, complex, and controversial disorder on the dissociative spectrum. The human brain is a magnificent tool, capable of breaking into pieces the conscious part of a person’s mind in order to protect the self from the memory of trauma. In DID (previously known as multiple-personality disorder), this means that at least two distinct personalities exist in one person, with one, or several, of the personalities (the “alters”) holding the memory of trauma away from the core personality so that he or she can function. Kaitlyn Johnson, as described by her (very negligent) doctor, is one such alter. What makes her unique is that she comes out only after dark and that—according to her—she has always been around and isn’t an alter at all, but a natural second half to her “sister.”

Kaitlyn was born during a period of my life when I experienced inversion syndrome (this is when you are awake at night, rather than during the day). During those nights, I began to think about what kind of life someone who had only ever known such darkness would have. What she would be like. How she would behave, how she would (or wouldn’t) associate with other people. And, of course, if there was a dark half to the equation in Kaitlyn, there had to be a light half. From that came Carly, someone who had only ever known warmth, light, and the reality of daily life. How different these two would be!

What might it be like to have control of only half your day? Would you love or resent the person who got the rest of it? Would you communicate with that person? How? What would it feel like not to have control of your own body—or worse, to feel as though your body may not even be yours?

What would it feel like to be told you are a symptom or a disease?

And then came the thought: What happens when the other half of your life is suddenly taken away? And what if someone told you the reason was not psychological (integration), but spiritual (demonic)? How would that feel?

Especially when no one will believe you’re real.

I would like to make a special thank-you to the person in my family who suffers with DID. You are the most intriguing person I know. All of you.

And another special thank-you to the doctors who gave me back control of my body.

This book is for you.

PHOTO CREDITS

Title page

Burnt paper: © istockphoto/sx70; doodle stars: © istockphoto/beastfromeast; old book: © istockphoto/najin; wood background: © istockphoto/sorendls

Part openers throughout

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Dr. Lansing Therapy Notes throughout

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