Twinless

Roman, a young man grieving the death of his identical twin Rocky in a car accident, joins a support group for twinless twins. He quickly befriends fellow attendee Dennis. In a perspective switch to Dennis, the audience learns that he went on a date with Rocky and slept with him shortly before Rocky's death, which he also indirectly caused. Dennis has lied about having a twin in order to get close to Roman.

Roman begins seeing Dennis' coworker Marcie, who doubts that Dennis ever had a twin brother. Marcie's investigation into Dennis' past confirms this and she confronts him, insisting that he tell Roman the truth.

Dennis and Roman attend a hockey game and share a hotel room afterwards. An intoxicated Dennis begins sucking on Roman's toes, and admits the deception. A flashback reveals that Dennis blames himself for Rocky's accident, having distracted Rocky just before the latter was hit by a car. A grieving Roman hits Dennis and leaves.

Roman and Dennis both struggle with their falling-out. Eventually, the two meet at a diner and discuss Rocky and their friendship. In unison, they ask a waitress for a to-go box.

• Dylan O'Brien as Roman / Rocky
• James Sweeney as Dennis
• Aisling Franciosi as Marcie
• Lauren Graham as Lisa, Rocky and Roman's mother
• Tasha Smith as Charlotte
• Chris Perfetti as George
• François Arnaud as Sammy
• Susan Park as Sage
• Cree Cicchino as Bianca

In February 2024, it was announced Dylan O'Brien had joined the cast of the film, with James Sweeney set to direct and co-star from a screenplay he wrote, David Permut set to produce and Republic Pictures set to distribute.^[3] In May 2024, Aisling Franciosi and Lauren Graham joined the cast of the film.^[4] In August 2024, Tasha Smith, Chris Perfetti, François Arnaud, Susan Park and Cree Cicchino joined the cast of the film.^[5]

Principal photography took place in Portland, Oregon.^[6]

Twinless premiered in the U.S. Dramatic Competition at the 2025 Sundance Film Festival on January 23, 2025.^[7] In April 2025, Republic Pictures sold the film to other studios for its theatrical release, with Lionsgate and Roadside Attractions acquiring the U.S. distribution rights and Sony Pictures Worldwide Acquisitions acquiring the international rights.^[8] It is scheduled to be released on September 5, 2025.^[9]

When the film was made available to festival viewers who opted to view the film remotely online during Sundance, graphic clips and GIFs from the film showing Dylan O'Brien's character having gay sex were leaked online by O'Brien's fans and shared across the social media platforms Twitter and Tumblr. The clips were later taken down after copyright infringement claims were filed, and the film itself was later removed from the Sundance online platform.^[10][11]

On the review aggregator website Rotten Tomatoes, 98% of 90 critics' reviews are positive. The website's consensus reads: "James Sweeney's sophomore outing reveals a twisty, grief-ridden journey of the unexpected -- buoyed by a perfectly sensitive Dylan O'Brien."^[12] Metacritic, which uses a weighted average, assigned the film a score of 80 out of 100, based on 23 critics, indicating "generally favorable" reviews.^[13] Audiences polled by CinemaScore gave the film an average grade of "A" on an A+ to F scale.^[14]

Benjamin Lee of The Guardian termed it a "dark, inventive comedy", adding that the "smart and highly unusual film earns its boundary-pushing because he never loses sight of the inescapable, human sadness at its core".^[15] The Hollywood Reporter's Lovia Gyarkye commended O'Brien's dual performances, and was appreciative of Sweeney's craft in "shifting between dry humor, gutting devastation and emotional poignancy".^[16]

Commenting on Sweeney's direction, Peter Debruge of Variety wrote, "On just his second film, the gifted young helmer demonstrates a sophisticated sense of framing, pace and exquisitely uncomfortable dramatic tension".^[17]