Josh Safdie’s latest film, Marty Supreme, which premiered in the United States on December 25, 2025, under the A24 banner, is already making waves—not just for its frenetic storytelling and period-perfect visuals, but for its audacious casting choices. The film, as reported by The New York Times on December 26, 2025, is a vivid, sometimes surreal, plunge into 1950s New York, centering on a gritty table tennis champion named Marty Mauser, played by Timothée Chalamet. Yet, in a year brimming with cinematic surprises, perhaps none is more unexpected than the performance of Kevin O’Leary—better known to millions as "Mr. Wonderful" from Shark Tank—as the enigmatic Milton Rockwell.
Director Josh Safdie, celebrated for his razor-sharp eye and unorthodox methods, had a vision for Marty Supreme: authenticity, down to the last follicle. Safdie’s casting director, Jennifer Venditti, told The New York Times, “Josh was, like, obsessed with hair. He did not want to use wigs.” The mandate was clear: no Mohawks, no bright white teeth, no shaved heads. The cast had to look as if they’d just stepped out of a black-and-white photograph from 1952. Venditti, known for blending seasoned actors with first-timers, faced the Herculean task of filling about 150 speaking roles, recruiting everyone from musicians and comedians to business moguls and supermarket tycoons. Among the most eye-catching choices were Tyler, the Creator, Tracy McGrady, John Catsimatidis, and, of course, O’Leary.
But how did a Canadian businessman with an estimated net worth of $400 million, as noted by Yahoo Entertainment, end up in one of the year’s buzziest films? The answer, fittingly, is as eccentric as O’Leary himself. According to Yahoo Entertainment, the journey began at O’Leary’s lake house, where Safdie and co-writer Ronald Bronstein trekked to read the script together. O’Leary, never one for Hollywood convention, insisted they come to him. “If they wanted me, they could sit on my dock and read the script together,” he recalled. The script, “the size of telephone books,” captivated a friend staying at the house, who urged O’Leary to take the role. When Safdie and his team arrived, they began reshaping the character around O’Leary’s own mannerisms and worldview. “They were quite flexible in crafting the story to the way I saw it to kind of melt into the character,” O’Leary said. “And it made it very easy for me to just slide into that role because, you know, I know how to be a billionaire in 1952. That’s not too far from what I do every day.”
O’Leary’s transition from boardroom titan to screen villain wasn’t without its challenges. Used to calling the shots, he had to adjust to ensemble work and take direction—something he admitted was a struggle. “I’ve never worked for anybody. So that’s very difficult,” he confessed to Yahoo Entertainment. The process, he said, required a leap of faith. He even relinquished control over his own contract, letting his longtime agent at UTA, Jay Sures, handle negotiations. “What I got paid, I have no idea,” O’Leary quipped. “I mean, I’ll be honest with you. I don’t know. Whatever I got, they negotiated it. I’m sure I’ll find out one day, but I don’t really give a shit.”
Safdie’s perfectionism was legendary on set. “He’s a perfectionist,” O’Leary said. “If one light isn’t perfect, he can’t start.” Scenes were shot and reshot—sometimes upwards of 40 takes—with Safdie and Bronstein occasionally arguing so intensely that they would "go yell at each other in the street." O’Leary, unaccustomed to such creative chaos, eventually embraced the process. “I’m pretty happy with the way that worked out,” he admitted, his trademark bravado intact.
Yet what truly sets O’Leary’s performance apart is how little acting he claims to have done. “I actually don’t think I was acting,” he told Yahoo Entertainment. “I don’t know what acting is. I don’t know what the rules of acting are.” Dyslexic and self-described as “really shitty at memorizing anything,” O’Leary relied on instinct and preparation. “I knew where we were in the story. I knew what was happening in the room. I could read the room.”
O’Leary’s Milton Rockwell is no mere cameo. As SlashFilm noted in a December 26, 2025 review, he delivers a full-blown supporting turn, stealing scenes with a devilish twinkle in his eye. Rockwell, a rich businessman who has built an empire through a pen company, is married to former actress Kay Stone (played by Gwyneth Paltrow). His path crosses with Chalamet’s Marty Mauser, a table tennis hustler with dreams of world championship glory. Their relationship is anything but straightforward. Rockwell, ever the opportunist, initially sees Marty as a business prospect. But when Marty’s headstrong nature torpedoes a lucrative deal, he’s forced to come crawling back, seeking Rockwell’s help to participate in a rigged match in China against Endo (Koto Kawaguchi), a player who had previously bested him.
One of the film’s most talked-about moments comes near the end, when Rockwell delivers a speech that is equal parts chilling and absurd. “Let me explain to you,” Rockwell intones, “I was born in 1601. I’m a vampire. I’ve been around forever. I’ve met many Marty Mausers over the centuries. Some of them crossed me, some of them weren’t straight. They weren’t honest. And those are the ones that are still here. You go out and win that game, you’re gonna be here forever too. And you’ll never be happy. You will never be happy.” The moment, as SlashFilm observes, is so ambiguous and bizarre that it lingers long after the credits roll. Is Rockwell being literal, or is this just another power play from a master manipulator? The film offers no answers, and that’s part of its enduring allure.
O’Leary’s performance is also marked by a scene that’s already become infamous: the so-called "butt-paddling" sequence. In an interview with The News International, O’Leary revealed that Chalamet refused a body double, insisting on authenticity. “That’s really Chalamet’s ass — he didn’t want the stunt double. I said, ‘Timmy, I’m going to have to belt your ass, are you sure you want to do this?’” O’Leary recounted. “He immortalized his ass on film for the rest of time. That scene freaks me out even now.”
For all its wild twists and genre-bending bravado, Marty Supreme is, at its core, a story about ambition, power, and the strange bedfellows they make. Safdie’s insistence on authenticity, from the haircuts to the casting, pays off in spades. And in the end, O’Leary’s leap from reality TV villain to cinematic antihero feels less like a stunt and more like a stroke of inspired, madcap genius. As O’Leary himself puts it: “To me, this is the pinnacle of filmmaking.”
It’s not every day you see a billionaire TV personality belt a Hollywood A-lister on screen or claim to be a centuries-old vampire. But then again, it’s not every day that a film like Marty Supreme comes along—defying expectations, blending reality and fiction, and leaving audiences with more questions than answers.
