‘The Love Hypothesis’ Shares Its Prime Video Spotlight With the Fisher Brothers, All Based on Hit Novels

Prime Video’s fall romance slate is bringing ‘The Love Hypothesis’ to streaming, and the film is arriving in the same conversation as two familiar faces from another beloved book adaptation. The film follows Olive, a Ph.D. candidate who kisses professor Adam Carlsen in a moment of desperation, only for the two to spiral into a fake relationship with rules, boundaries and a mutually beneficial agreement. ‘The Love Hypothesis’ is set to premiere on September 23, 2026, with Lili Reinhart, Tom Bateman and Rachel Marsh leading the cast under director Claire Scanlon.

What makes this release window notable is not just the film itself, but the company it is keeping. Prime Video has also been spotlighting the Fisher brothers from ‘The Summer I Turned Pretty,’ with Christopher Briney and Gavin Casalegno each appearing in their own upcoming projects on the platform. The overlap has given fans of both franchises a reason to pay attention to Prime Video’s broader romance and coming of age lineup this season.

The Love Hypothesis Is Based on Ali Hazelwood’s Bestselling Novel

‘The Love Hypothesis’ is a romance novel by Ali Hazelwood, first published on September 14, 2021 by Berkley Books, and it has since sold over 750,000 copies worldwide. The book began as Reylo fan fiction, an imagined romance between the ‘Star Wars’ characters Rey and Kylo Ren, before Hazelwood reworked the premise into a contemporary academic romance. That origin story has become one of the most talked about parts of the film’s rollout, since it explains several of the character choices readers will recognize.

In the novel, Olive Smith is a third year biology Ph.D. student at Stanford University who fakes a relationship with Dr. Adam Carlsen to convince her friend Anh that she has moved on from her ex boyfriend. The film adaptation is directed by Claire Scanlon from a screenplay by Sarah Rothschild, and it is produced by Elizabeth Cantillon for MRC’s Bisous Pictures and the Cantillon Company.

Amazon MGM Studios is distributing the film through Prime Video, with cinematography by Matthew Clark and a score from Laura Karpman. The adaptation has been years in the making, giving Hazelwood’s growing fan base ample time to speculate about casting before the first footage ever arrived.

Lili Reinhart and Tom Bateman Lead the Cast of The Love Hypothesis

Tom Bateman plays Dr. Adam Carlsen opposite Lili Reinhart as Olive Smith, with Rachel Marsh as Anh, Jaboukie Young-White as Malcolm, Nicholas Duvernay as Jeremy and Arty Froushan as Tom Benton rounding out the central cast. Bateman is known for the murder mystery films ‘Murder on the Orient Express’ and ‘Death on the Nile,’ along with the series ‘Da Vinci’s Demons’ and ‘Based on a True Story.’

Part of the intrigue around Bateman’s casting comes from his own marriage. He is married to ‘Star Wars’ actress Daisy Ridley, who played Rey, the character Olive is loosely based on, and who was also his co-star in ‘Murder on the Orient Express.’ That coincidence has followed the film through nearly every piece of promotional coverage since it was announced.

Hazelwood has voiced her approval of the ensemble, confirming she is fully on board with how the actors are portraying her characters. Reinhart confirmed filming had wrapped through a September 2025 social media post, in which she and Bateman jokingly reenacted a farewell scene from ‘The Office.’

Speaking with Marie Claire ahead of the release, Reinhart discussed the challenge of grounding Hazelwood’s heightened romance dialogue on screen, telling the outlet that she worked to make the story feel as organic as possible even when the source material’s lines did not always roll naturally off the tongue in the interview for its Next Gen Issue cover story.

The Fisher Brothers Get Their Own Spotlight Alongside The Love Hypothesis

Prime Video’s first footage reveal for ‘The Love Hypothesis’ arrived as part of a larger sizzle reel that also featured ‘The Summer I Turned Pretty’ stars Christopher Briney and Gavin Casalegno previewing their newest Prime Video projects. Casalegno is known for playing Jeremiah Fisher in ‘The Summer I Turned Pretty,’ while Briney plays his on screen brother Conrad.

According to Deadline, the pairing was not incidental to the presentation. The outlet reported that both Fisher brothers, alums of a series now shooting its final film installment, were set to appear in their respective new projects as part of the same summer slate highlighted alongside ‘The Love Hypothesis.’

Briney is starring in ‘Clashing Through the Snow’ opposite Michelle Randolph, while Casalegno appears in ‘The Devil’s Mouth’ alongside Kathryn Newton and Lana Condor. Both projects were teased in the same footage drop that gave audiences their first extended look at Reinhart and Bateman as Olive and Adam.

The grouping underscores how heavily Prime Video is leaning on familiar faces from its existing young adult hits to cross promote its 2026 romance slate. Viewers who came to the platform for ‘The Summer I Turned Pretty’ are, by design, being pointed toward ‘The Love Hypothesis’ and vice versa.

The Love Hypothesis Release Date on Prime Video

‘The Love Hypothesis’ releases exclusively on Prime Video globally on September 23, and the service is included with an Amazon Prime membership. Reinhart also serves as an executive producer on the adaptation, alongside her role leading the cast as Olive Smith.

The release date lands squarely in what fans online have jokingly called pumpkin spice latte season, a detail Prime Video itself leaned into when confirming the premiere. With the Fisher brothers’ own projects rolling out around the same period, Prime Video appears to be positioning the fall as a broader event for fans of book to screen romance.

For readers who grew up on Conrad and Jeremiah’s story and are now watching Olive and Adam’s fake relationship unfold, this shared spotlight raises an obvious question worth discussing, whether ‘The Love Hypothesis’ can carry the same devotion that turned ‘The Summer I Turned Pretty’ into appointment viewing.