Twinless opens on a static sH๏τ of a storefront – in the background, we hear tires screech before a car collides with what is presumably a person. The film then cuts to a funeral where Roman (Dylan O’Brien) and his mother (Lauren Graham) are mourning the death of Roman’s twin brother Rocky. Mourners give their condolences, with many unable to look at Roman without comparing him to his now-ᴅᴇᴀᴅ brother.

In writer-director James Sweeney’s second film, in which he also stars, a simple premise blooms into something altogether unhinged in increasingly surprising ways. Sweeney stars as Dennis, a sweet, quick-witted guy who is immediately enamored with Roman when they meet in a grief support group for twins who have lost a sibling. Roman doesn’t mind the attention from Dennis – he’s glad to have the company, which quickly develops into a lightly toxic co-dependent friendship.

Sweeney’s script has a few tricks up its sleeve and from this friendship, Twinless reveals a deft balancing act between its story about grief-stricken men and a psycH๏τic cringe comedy that is as squirm-inducing as it is hysterical. Neither Roman nor Dennis are particularly likable, but Twinless maintains an empathy for these two despite their obvious and often destructive flaws.

Twinless Takes A Bold Approach To Its Subject Matter

Sweeney & O’Brien Don’t Hold Back

You see, Dennis never actually had a twin. In flashback, we see a mustached O’Brien as the extroverted Rocky, who seduces the fragile Dennis in a one-night affair. Dennis quickly grows attached to Rocky, but his affection is not reciprocated and Dennis seeks out Roman as a replacement after Rocky’s death. Sweeney sells Dennis’ obsession with a stellar performance, but O’Brien makes it easy to see why the lonely introvert would be infatuated with them.

As Rocky and Roman, O’Brien is like we’ve never seen him before, exuding a cool, magnetic confidence that stands in stark contrast to Roman’s deep loneliness. As a salve to this loneliness, Dennis is quite healing – he goes grocery shopping with Roman and corrects him when he uses incorrect words and turns of phrase. Roman is not the smartest, more of a meathead than anything, but this is what endears him to Dennis.

Sweeney makes sure to give Dennis just as much depth. Though we see things from his perspective for most of the film, his background remains vague as his reliability is called into question. Still, it’s clear he’s lonely, too. He sits above Portland in his high-rise apartment, looking down at the city through floor-to-ceiling windows. He watches old Mary-Kate and Ashley movies, saying the lines along with the stars.

His self-professed obsession with twins is both fetishistic and profoundly sad. We see him at his office job where he mostly talks with receptionist Marcie (Aisling Franciosi, in a delightful supporting turn) and even as Dennis looks down at all those around him, there’s a similar magnetism to him despite his emotional manipulation. That Sweeney manages to maintain some levity and empathy with Dennis is a feat.

Even though their relationship is built on a lie, there is something sweet about Dennis and Roman’s bond. The loneliness they both feel leaves them vulnerable to the ways that this co-dependent bromance can help them. Roman gets to accept his brother’s idenтιтy in a way he was never able to when Rocky was alive and Dennis gets the sibling he always wanted.

In the end, it’s actually quite beautiful and Twinless ends on a bizarrely hopeful note despite the emotional carnage that comes before it. Sweeney found the perfect partner in O’Brien, who has proven he is willing to take risks in recent roles, including last year’s Sundance movie Ponyboi.

Twinless is designed to make you squirm, but it’s through this discomfort that Sweeney finds humor and heart. In their loneliness, Dennis and Roman do unforgivable things, but the bond they share in their different shades of grief can often trump the more transgressive acts of longing and retaliation that occur.

Twinless premiered at the 2025 Sundance Film Festival on January 23.