It’s only been four short years since Ali Hazelwood’s debut novel, The Love Hypothesis, took the romance genre by storm, landing on The New York Times Best Sellers list and staying there for a 40-plus weeks.
Rather than resting on her laurels, however, the writer rolled up her sleeves and got to work, churning out not one, not two, but seven more novels (plus a Spotify novella) since then, with two more on the way for 2025.
It was a radical shift for the former neuroscience professor, whose STEM-focused plots were drawn directly from her experiences as a woman in the field. “When I started my Ph.D., I was the only woman in my cohort, and it felt kind of isolating,” she told WGBH in 2023.
Now, she's resonating with readers worldwide—especially an audience on #BookTok—with her ultra-steamy tales of brainy romance. Her latest, Problematic Summer Romance, which hits shelves on May 27, revisits Maya and Conor’s story from her 2024 novel Not in Love; and her 2024 paranormal love story Bride will get a sequel, Mate, later this year on October 7.
“Whenever I write a book, all I ever hope is that it will help people to pass a couple of hours without thinking of whatever it is that bothers them in real life,” Hazelwood told Woman’s World. "Also, I love smut!”
If you, too, love a good smutty romance, you’ve come to the right place: We ranked the author's best novels from the STEM-iest to the steamiest. Check out the best Ali Hazelwood books ranked below.
Not in Love delivers on the kink relatively early, but Eli’s obsession with Rue—and alternately, her nonchalant attitude toward him—left some readers not in love with its pages. The plot here is also less developed than some of her works, landing it lower on our list of Hazelwood’s best. That said, if you’re looking for a quick and dirty (emphasis on the dirty) read, this book—about a biotech engineer at a food science start-up and the executive who wants to buy the business she works for—does the trick.
2022 was a busy year for Hazelwood: The romance novelist published three separate novellas, all of which can be found in 2023’s Loathe to Love You. In short? It serves up different romances (Under One Roof, Stuck with You, and Below Zero) in one, making for a great introduction to the world of Hazelwood, so long as you’re okay with some common themes and tropes. It’s also a good pick for those who can’t stand a slow burn, since novellas require a faster pace, as Hazelwood explained to She Writes. “There isn’t as much room to introduce the characters to the readers, so I find that it’s necessary to put the characters in stressful situations from the very start—which is a lot of fun!”
Love on the Brain cemented Hazelwood’s reigning title as a “STEMinist.” It also left fans deeply divided on Reddit. For those who liked The Love Hypothesis and wanted something similar, Hazelwood’s second novel—a rom-com between the lead on a NASA project and her professional enemy—didn’t disappoint, revisiting everything from its super smart leads to its copious science references. For others, it was a bit too similar for enjoyment and less than progressive where it mattered most (in the bedroom).
Hazelwood took a step back from the world of STEM to mixed results with 2025’s Deep End, which she has described as a “college romance between a swimmer and a diver.” Fans gave Scarlett Vandermeer (a.k.a. Vandy) and Lukas Blomqvist's X-rated tale middling reviews, but it’s the first one you’ll want to grab if you’re here for the racy bits. Originally called Whet, it’s been widely hailed as Hazelwood’s most blush-inducing work yet. Fifty Shades of moist, anyone?
If you were the target audience for Adam Driver’s shirtless scene in Star Wars: The Last Jedi, you’ll be delighted to know that Hazelwood’s debut novel, The Love Hypothesis, actually started as a fan fiction piece about the budding romance between Driver’s Kylo Ren and Rey (Daisy Ridley). Sure, the plot has been changed a bit: “Olive” is a Ph.D candidate who finds herself living out a faux relationship with an arrogant lab professor named (what else?) Adam—a seemingly far cry from light saber battles and Jedi mind tricks. But the unlikely bond that grows between these two wildly different personalities (and Adam’s undeniable six-pack) will certainly ring some bells.
2024’s Not in Love didn’t exactly have Hazelwood readers gushing over its prose, but its follow-up novel, Problematic Summer Romance, just might. In fact, one Goodreads reviewer called it “Hazelwood’s best yet.” Focusing on the first book’s secondary characters of Maya (that’s Eli Killgore’s sister, in case you need a refresher) and his friend and business co-founder Conor, it plays on the trope of a May-December romance as this unlikely duo finds themselves thrown together at a destination wedding. Sexual tension amid a picturesque Southern Italian backdrop? Can you say “swoon?”
Don’t let the “young adult” label fool you—Check & Mate is one of Hazelwood’s best works. It’s also the one Hazelwood says she was most passionate about bringing to life. “It’s definitely the book that I wanted to write the most,” she told the Boston Globe in 2023. She explained that she had envisioned the plot about a talented chess player who leaves the game behind for personal reasons, only to get sucked back in after defeating the No. 1 player in the world, as far back as 2018. Given its target audience, it’s less naughty, more sweet (think The Queen’s Gambit, but more uplifting), but honestly, it works just the same.
When you think you’ve got Hazelwood pegged as an author, she surprises with a star-crossed love story between a werewolf and a vampyre. Despite being a complete departure from her usual tropes, it wasn’t completely out of left field: Hazelwood told the "Creative Inspired Happy" podcast that she negotiated to have Bride included in her contract on the heels of her The Love Hypothesis success. Her bargaining paid off: Readers found it entertaining, emotional, among 2024's best romance novels, and top-three-worthy. Soon, it will see a successor in October’s Mate.
Poll Ali Hazelwood’s fans online, and one book in her repertoire pops up more than any other as a fan favorite: Love, Theoretically. Hazelwood’s third novel was inspired by the trope of dating someone under false pretenses…with a plot twist. “I really wanted to write a story in which the main character is someone who sort of puts on a mask constantly, but there is this one person who was able to see through that mask and really see the kind of person she is,” Hazelwood told WGBH. The result? Rave reviews galore and a swoon-inducing romance between theoretical physicist Elsie Hannaway and the experimental physicist who just so happens to be her biggest professional threat.
What is the spiciest Ali Hazelwood book?
Multiple outlets, ranging from USA TODAY to The Every Girl, have dubbed Hazelwood’s Deep End as her spiciest novel for its portrayal of Vandy and Lukas’s kink BDSM scenes.
As one Goodreads reader opined, “This is everything Fifty Shades thought it was and also they have the stamina of Olympic athletes.”
If bondage isn’t exactly your bag, however you can reach for Bride or Not in Love, both of which are also on the more explicit side of Hazelwood’s catalog.
Who else should I read if I like Ali Hazelwood?
If you like Ali Hazelwood, other contemporary romance novelists, like Emily Henry and Tessa Bailey, might be right up your alley.
Hazelwood also has some of her own recommendations, citing Sherry Thomas’s The One in My Heart as an inspiration and shouting out Denise Williams’s Technically Yours and Jo Segura’s Raiders of the Lost Heart on social media. “Both these books 1) are VERY STEAMY 🔥 2) contain MMCs who fall first and hard and then pine for YEARS 💅 3) are our today ✅ One is set in STEM and one in archeology and they’re both AMAZING,” she gushed on Instagram.
What is Ali Hazelwood’s best-selling book?
Hazelwood’s debut novel, The Love Hypothesis, is by far her best-selling book.
“My first book was very successful, but none of my other books have been as successful,” she said on "Creative Inspired Happy" in 2024, noting that she has had to find other ways to measure "success" as her career has progressed.
“[In 2022], I was full of anxiety and I was like, “Oh, my God, people aren’t going to like my other books and nothing is ever going to compare,’” she confessed to GBH.
However, Hazelwood has come a long way since then, telling the outlet, “I am not very anxious about it anymore, and I think it's because I have completely cut myself off [from] any sort of online basis…If people don't like the book, I will never know. And that is beautiful.”
