The path to this book was a long one and I have many people to thank. Above all, I need to start with Adam, Ezra, Lily, Jonah—and Zishe. They inspire me every day with their unwavering belief that I can fix any problem and rewrite any scene. They are my first readers and my last. I can never thank them enough. Especially Adam for leading the charge.

Thank you, thank you to my parents, Sol and Edna. And to my second parents, Nancy and Jerry. To my siblings, who know exactly when I need someone to remind me that everything is going to work out somehow: Aaron, Adam, Jen, Joshua, Joshua, Nicole, Sarah, and Stacey.

I am grateful beyond measure to my mighty, mighty editor Millicent Bennett who has labored over every word with me and understood from the beginning that writing is love. And I can never thank the phenomenal Eve Attermann enough. She is my dream agent in every way, a woman who understands what I mean no matter how convoluted it may appear in a first draft or when I spill my guts on the phone. You two are a dream team. No writer could ever ask for more. Thank you.

Marjorie Gellhorn Sa’adah was the first to ask: If you love writing so much, why are you wasting time on anything else? I couldn’t be more grateful for that, and for her teaching and mentorship. Thank you to Beverly Horowitz, who reminded me again and again to get inside a character’s head—and to just keep writing. To Karun Grossman and Judah Grossman, who taught me to write a better fight scene. To Linda Kleinbaum and Steve Anderson, who made sure I got to the point faster. To Sylvia Horowitz, who braved even the roughest early drafts. To Hilary Ryder, who offered crucial medical advice; any mistakes that remain are my own. To Matthew Henken, who helped me through those first one hundred pages—on my one hundredth pass. To Rebecca Makkai, who pointed out exactly what worked and what needed to go. To Erin Harris, who did the same—helping me slash pages. To Clio Seraphim for her brilliant eye and early cheers. To Joanna Josephson, Elizabeth Posner-Navisky, and Ernest Sachs, who read my earlier books that weren’t up to snuff but still pushed me to keep writing. To Joni Cole and her Writer’s Center in White River Junction, who got me to start all over again. To Ryan Hickox, who helped me untangle Einstein and his field equations; all mistakes that remain are my own. And to Miriam Udel, whose expert knowledge helped me check several facts at the last hour. Again, all mistakes that remain are my own.

The incredible Michelle Hoover and her Novel Incubator are the best thing that ever happened to my writing. An enormous thank you to Michelle and to my NI5 classmates: Louise Berliner, Helen Bronk, Denis Carey, Janet Rich Edwards, Robert Fernandes, Jen Johnson, Ayaz Mahmud, Andrea Meyer, and Tracey Palmer. And especially to those of you who kept reading—and keep reading. Thank you to all of Michelle’s alums, especially Susan Bernhard, Colwill Brown, Michele Ferrari, Kelly Ford, Louise Miller, Alison Murphy, Patricia Park, Julia Rold, Emily Ross, Elizabeth Shelburne, and Jennie Wood. All of you have gone above and beyond to help me at some point and I truly appreciate it. To Marc Foster for opening his family home for retreats and for talking engineering. And a huge thank you to Jenna Blum for introducing me to Grub Street in the first place.

Eve Bridburg, thank you for building the amazing Grub Street with Christopher Castellani and so many others I can’t even name them all. To Chris in particular, your advice is always brilliant and appreciated more than you know. As I tell you all the time, you make my writing world a lot less lonely and you’ve inspired me to dive in headfirst. I can’t thank you enough for that. Thank you to Sonya Larson and Hanna Katz for the Muse. To the Grub staff, teachers, supporters, donors, and incredible fundraisers who made my scholarship possible: Thank you. You changed my life.

A big, huge, giant thank-you to my exceptional team at Grand Central. Andy Dodds, your energy and enthusiasm are infectious and your talent is unmatched. I cannot thank you enough for all you’ve done to launch this book into the world. Other incredible team members that I’d like to thank include Ben Sevier, Karen Kosztolnyik, Beth deGuzman, Brian McLendon, Alana Spendley, Meriam Metoui, Anjuli Johnson, Angelina Krahn (who can spot a homophone from a mile away), Karen Torres (whose love of the book pushed me to believe it was all going to come together), Chris Murphy, Alison Lazarus, Ali Cutrone, and the rest of the incomparable sales team at GCP.

A huge thank-you to the WME team that always pulls me back together again. Haley Heidemann—you rock. Thank you to Matilda Forbes Watson and Alina Flint for careful reads and critiques early on. And thank you to the amazing duo on my international sales team, Svetlana Katz and Siobhan O’Neill.

As for the text itself, thank you to Vladimir Nabokov and Robert Mann for their artful English translations of the Song of Igor’s Campaign. I used a sentence from each in the text. And thank you to George Bruce Halsted. I used his 1913 English translation of Poincaré’s 1898 publication “The Measure of Time” in the epigraph. Thank you to Eric Kimmel for his version of Gershon’s Monster, which reminded me of the tale I’d heard decades ago from Rabbi Cynthia Kravitz, who loved nothing more than sharing a good story. I may have acted like I wasn’t listening but I was hanging on your every word. “Levi’s Monster” in this book is based on the many versions of this old folktale.

While writing a book is a solitary endeavor, publishing is not. Dozens and dozens of people are involved in the magic that pulls a manuscript together, and while I’m hoping I’ve thanked everyone, I need to apologize to anyone I might have missed. Truly, I could not have polished this book and sent it out into the world without the army of helpers at WME and Grand Central, and my family and friends cheering along the way. You all matter more than you could ever know. Thank you.