PRAISE FORThe Love Hypothesis“Contemporary romance’s unicorn: the elusive marriage ofdeeply brainy and delightfully escapist. . . .The LoveHypothesis has wild commercial appeal, but the quietersecret is that there is a specific audience, made up of allthe Olives in the world, who have deeply, ardently waitedfor this exact book.”—New York Times bestselling author ChristinaLauren “Funny, sexy, and smart. Ali Hazelwood dida terrific job withThe Love Hypothesis.”—New York Times bestselling author MarianaZapata “This tackles one of my favorite tropes—Grumpy meets Sunshine—in a fun and utterlyendearing way. . . . I loved the nods towardfandom and romance novels, and I couldn’t put itdown. Highly recommended!”—New York Times bestselling author Jessica Clare“A beautifully written romantic comedy with aheroine you will instantly fall in love with,TheLove Hypothesis is destined to earn a place onyour keeper shelf.”—Elizabeth Everett, author ofA Lady’s Formulafor Love “Smart, witty dialogue and a diverse castof likable secondary characters. . . . A realistic,amusing novel that readers won’t be able to putdown.”—Library Journal (starred review) “With whip-smart and endearing characters, snappy prose,and a quirky take on a favorite trope, Hazelwoodconvincingly navigates the fraught shoals of academia. . . .This smart, sexy contemporary should delight a wide swathof romance lovers.”—Publishers Weekly Titles by Ali HazelwoodThe Love HypothesisLOATHE TO LOVE YOUUnder One RoofStuck with YouBelow Zero Below ZeroAli HazelwoodJOVENEW YORK A JOVE BOOKPublished by BerkleyAn imprint of Penguin Random House LLCpenguinrandomhouse.comCopyright © 2022 by Ali Hazelwood Excerpt fromLove on the Brain copyright © 2021 by AliHazelwood Penguin Random House supports copyright. Copyright fuels creativity, encourages diversevoices, promotes free speech, and creates a vibrant culture. Thank you for buying an authorizededition of this book and for complying with copyright laws by not reproducing, scanning, ordistributing any part of it in any form without permission. You are supporting writers and allowingPenguin Random House to continue to publish books for every reader.A JOVE BOOK, BERKLEY, and the BERKLEY & B colophon are registered trademarks of PenguinRandom House LLC. Ebook ISBN: 9780593437834Jove audio edition: April 2022Jove ebook edition: July 2022Cover illustration by lilithsaur Adapted for ebook by Cora Wigen This is a work of fiction. Names,characters, places, and incidents either are the product of the author’s imagination or are usedfictitiously, and any resemblance to actual persons, living or dead, business establishments, events, orlocales is entirely coincidental.pid_prh_6.0_140348893_c0_r0 ContentsCoverPraise for The Love HypothesisTitles by Ali HazelwoodTitle PageCopyrightDedicationPrologueChapter 1Chapter 2Chapter 3Chapter 4Chapter 5Chapter 6Chapter 7Chapter 8Chapter 9EpilogueExcerpt from Love on the BrainAbout the Author For Shep and Celia. Still with no polar bears, but with lotsof love. PrologueSvalbard Islands, Norway PresentI dream of an ocean.Not the Arctic, though. Not the one right here inNorway, with its close-packed, frothy waves constantlycrashing against the coasts of the Svalbard archipelago. It’sperhaps a bit unfair of me: the Barents Sea is perfectlyworth dreaming of. So are its floating icebergs andinhospitable permafrost shores. All around me there isnothing but stark, cerulean beauty, and if this is the placewhere I die, alone and shivering and bruised and prettydamn hungry . . . well, I have no reason to bitch.After all, blue was always my favorite color.And yet, the dreams seem to disagree. I lie here, in myhalf-awake, half-unconscious state. I feel my body yieldprecious degrees of heat. I watch the ultraviolet morninglight reach inside the crevasse that trapped me hours ago,and the only ocean I can dream of is the one on Mars.“Dr. Arroyo? Can you hear me?”I mean, this entire thing is almost laughable. I am aNASA scientist. I have a doctorate in aerospaceengineering and several publications in the field ofplanetary geology. At any given time, my brain is a jumbledmaelstrom of stray thoughts on massive volcanism, crystalfluid dynamics, and the exact kind of anti-radiationequipment one would need to start a medium-size human colony on Kepler-452b. I promise I’m not being conceitedwhen I say that I know pretty much all there is to knowabout Mars. Including the fact that there are no oceans onit, and the idea that there ever were is highly controversialamong scientists.So, yeah. My near-death dreams are ridiculousandscientifically inaccurate. I would laugh about it, but I havea sprained ankle and I’m approximately ten feet below theground. It seems better to just save my energy for what’s tocome. I never really believed in an afterlife, but whoknows? Better hedge my bets.“Dr. Arroyo, do you copy?”The problem is, it calls to me, this nonexistent ocean onMars. I feel the pull of it deep inside my belly, and it warmsme even here, at the icy tip of the world. Its turquoisewaters and rust-tinted coastlines are approximately 200million kilometers from the place where I’ll die and rot, butI cannot shake the feeling that they want me closer. Thereis an ocean, a network of gullies, an entire giant planet fullof iron oxide, and they’re all calling to me. Asking me togive up. Lean in. Let go.“Dr. Arroyo.”And then there are the voices. Random, improbablevoices from my past. Well, okay:a voice. It’s always thesame, deep and rumbling, with no discernible accent andwell-pronounced consonants. I don’t really mind it, I mustsay. I’m not sure why my brain has decided to impose it onme just now, considering that it belongs to someone whodoesn’t like me much—someone I might like even less—butit’s a pretty good voice. A+. Worth listening to in a death’sdoor situation. Even though Ian Floyd was the one whonever wanted me to come here to Svalbard in the firstplace. Even though the last time we were together he was stubborn, and unkind, and unreasonable, and now heseems to sound only . . .“Hannah.”Close. Is this really Ian Floyd? Soundingclose?Impossible. My brain has frozen into stupidity. It mustreally be all over for me. My time has come, the end isnigh, and—“Hannah. I’m coming for you.”My eyes spring open. I’m not dreaming anymore. Chapter 1Johnson Space Center, Houston, U.S.One year agoOn my very first day at NASA, at some point between theHR intake and a tour of the Electromagnetic ComplianceStudies building, some overzealous newly hired engineerturns to the rest of us and asks, “Don’t you feel like yourentire life has led you to this moment? Like you weremeantto be here?”Aside from Eager Beaver, there are fourteen of usstarting today. Fourteen of us fresh out of top-five graduateprograms, and prestigious internships, and CV-beefingindustry jobs accepted exclusively to look more attractiveduring NASA’s next round of recruitment. There’re fourteenof us, and the thirteen that aren’t me are all noddingenthusiastically.“Always knew I’d end up at NASA, ever since I was like,five,” says a shy-looking girl. She’s been sticking by my sidefor the entire morning, I assume because we’re the onlytwo non-dudes in the group. I must say, I don’t mind it toomuch. Perhaps it’s because she’s a computer engineerwhile I’m aerospace, which means there’s a good chancethat I won’t see much of her after today. Her name isAlexis, and she’s wearing a NASA necklace on top of aNASA T-shirt that only barely covers the NASA tattoo onher upper arm. “I bet it’s the same for you, Hannah,” she adds, and I smile at her, because Sadie and Mara insistedthat I shouldn’t be my resting-bitch self now that we live indifferent time zones. They are convinced that I need tomake new friends, and I have reluctantly agreed to put in asolid effort just to get them to shut up. So I nod at Alexislike I know exactly what she means, while privately I think:Not really.When people find out that I have a Ph.D., they tend toassume that I was always an academically driven child.That I cruised through school my entire life in a constanteffort to overachieve. That I did so well as a student, Idecided to remain one long after I could have booked it andfreed myself from the shackles of homework and nightsspent cramming for never-ending tests. People assume, andfor the most part I let them believe what they want. Caringwhat others think is a lot of work, and—with a handful ofexceptions—I’m not a huge fan of work.The truth, though, is quite the opposite. I hated school atfirst sight—with the direct consequence that school hatedthe sullen, listless child that I was right back. In the firstgrade, I refused to learn how to write my name, eventhoughHannah is only three letters repeated twice. Injunior high, I set a school record for the highest number ofconsecutive detention days—what happens when youdecide to take a stand and not do homework for any of yourclasses because they are too boring, too difficult, toouseless, or all of the above. Until the end of my sophomoreyear, I couldn’t wait to graduate and leave all of schoolbehind: the books, the teachers, the grades, the cliques.Everything. I didn’t really have a plan forafter, except forleavingnow behind.I had this feeling, my entire life, that I was never goingto beenough. I internalized pretty early that I was never going to be as good, as smart, as lovable, as wanted as myperfect older brother and my flawless older sister, and afterseveral failed attempts at measuring up, I just decided tostop trying. Stop caring, too. By the time I was in my teens,I just wanted . . .Well. To this day, I’m not sure what I wanted at fifteen.For my parents to stop fretting about my inadequacies,maybe. For my peers to stop asking me how I could be thesibling of two former all-star valedictorians. I wanted tostop feeling as though I were rotting in my ownaimlessness, and I wanted my head to stop spinning all thetime. I was confused, contradictory, and, looking back,probably a shitty teenager to be around. Sorry, Mom andDad and the rest of the world. No hard feelings, eh?Anyhow, I was a pretty lost kid. Until Brian McDonald, ajunior, decided that asking me to homecoming by openingwith “Your eyes are as blue as a sunset on Mars” might getme to say yes.For the record, it’s a horrifying pickup line. Do notrecommend. Use sparingly. Use not at all, especially if—likeme—the person you’re trying to pick up has brown eyesand is fully aware of it. But what was an undeniable lowpoint in the history of flirting ended up serving, if you’llforgive a very self-indulgent metaphor, as a meteorite ofsorts: it crashed into my life and changed its trajectory.In the following years, I would find out that all of mycolleagues at NASA have their own origin story. Their veryown space rock that altered the course of their existenceand pushed them to become engineers, physicists,biologists, astronauts. It’s usually an elementary school tripto the Kennedy Space Center. A Carl Sagan book under theChristmas tree. A particularly inspiring science teacher atsummer camp. My encounter with Brian McDonald falls under that umbrella. It just happens to involve a guy who(allegedly) went on to moderate incel message boards onReddit, which makes it just a tad lamer.People obsessed with space are split into two distinctcamps. The ones who want togo to space and crave thezero gravity, the space suits, drinking their own recycledurine. And there’re people like me: what we want—oftentimes what we’ve wanted since our frontal lobes werestill undeveloped enough to have us thinking that toe shoesare a good fashion statement—is toknow about space. Atthe beginning it’s simple stuff: What’s it made of? Wheredoes it end? Why do the stars not fall and crash onto ourheads? Then, once you’ve read enough, the big topics comein: Dark matter. Multiverse. Black holes. That’s when yourealize how little we understand about this giant thingwe’re part of. When you start thinking about whether youcan help produce some new knowledge.And that’s how you end up at NASA.So, back to Brian McDonald. I didn’t go to homecomingwith him. (I didn’t go to homecoming at all, because itwasn’t really my scene, and even if it had been, I wasgrounded for failing an English midterm, and even if Ihadn’t been, fuck Brian McDonald and his poorlyresearched pickup lines.) However, something about thewhole thing stuck with me. Why would a sunset be blue?And on a red planet, no less? It seemed like somethingworth knowing. So I spent the night in my room, googlingdust particles in the Martian atmosphere. By the end of theweek, I’d signed up for a library card and devoured threebooks. By the end of the month, I was studying calculus tounderstand concepts like thrust over time and harmonicseries. By the end of the year, I had a goal. Hazy, confused,not yet fully defined, but a goal nonetheless. For the first time in my life.I’ll spare you most of the grueling details, but I spent therest of high school busting ass to make up for the ass Ihadn’t busted for the previous decade. Just picture an ’80straining montage, but instead of running in the snow anddoing pull-ups with a repurposed broomstick, I was hard atwork on books and YouTube lectures. And it washard work:wanting to understand concepts like H-R diagrams orsynodic periods or syzygy did not make them any easier tograsp. Before, I’d never reallytried. But at the tender ageof sixteen, I was confronted with the unbearable turmoilthat comes with trying your best and realizing thatsometimes it simply isn’t enough. As much as it pains me tosay it, I don’t have an IQ of 130. To really understand thebooks I wanted to read, I had to review the same conceptsover, and over, and fuckingover again. Initially I coasted onthe high of finding out! new! things!, but after a while mymotivation began to wane, and I started to wonder what Iwas even doing. I was studying a bunch of really basicscience stuff, to be able to graduate to more advancedscience stuff, so that one day I’d actually know all thescience stuff about Mars and . . . and what then? Go onJeopardy! and pick Space for 500? Didn’t really seem worthit.Then August of 2012 happened.When theCuriosity rover approached the Martianatmosphere, I stayed up until one A.M. I chugged down twobottles of Diet Coke, ate peanuts for good luck, and whenthe landing maneuver began, I bit into my lip until it bled.The moment it safely touched the ground I screamed, Ilaughed, I cried, and then got grounded for a week forwaking up the entire household the night before mybrother left for his Peace Corps trip, but I didn’t care. In the following months I devoured every little piece ofnews NASA issued onCuriosity’s mission, and as Iwondered about who was behind the images of the GaleCrater, the interpretation of the raw data, the reports onthe molecular composition of the Aeolis Palus, my hazy,undefinable goal began to solidify.NASA.NASA was the place to be.The summer between junior and senior years, I found aranking of the hundred best engineering programs in theU.S. and decided to apply to the top twenty. “You shouldprobably extend your reach. Add a few safety schools,” myguidance counselor told me. “I mean, your SATs are reallygood and your GPA has improved a lot, but you have abunch of”—long pause for throat clearing—“academic redflags on your permanent record.”I thought about it for a minute. Who would have figuredthat being a little shit for the first one and a half decades ofmy life would bring lasting consequences? Not me. “Okay.Fine. Let’s do the top thirty-five.”As it turns out, I didn’t need to. I got accepted to awhopping (drumroll, please) . . . one top-twenty school. Areal winner, huh? I don’t know if they misfiled myapplication, misplaced half of my transcripts, or had a brainfart in which the entire admissions office temporarily forgotwhat a promising student is supposed to look like. I putdown my deposit and approximately forty-five seconds aftergetting my letter told Georgia Tech that I’d be attending.No backsies.So I moved to Atlanta, and I gave it my all. I chose themajors and the minors I knew NASA would want to see on aCV. I got the federal internships. I studied hard enough toace the tests, did the fieldwork, applied to grad school,