One of the most talked-about scenes in Christopher Nolan’s The Odyssey features the titular Odysseus facing off against the Laestrygonians, the giant armoured cannibals of Homer’s epic. There is just one catch: the impressive pair of arms audiences see on screen do not belong to Matt Damon.Days after the film’s release, Damon revealed that his double in the sequence was 35-year-old stuntwoman Devyn Dalton, who, he told podcaster Josh Horowitz, has “the greatest arms I’ve ever seen”.There is another apparent mismatch. Dalton is 4’6” tall, while Damon is a fairly average 5’10”. Her smaller stature was in fact part of the point: smaller stunt performers helped make Odysseus and his men appear dwarfed by the gigantic Laestrygonians.For Dalton, the answer is fairly straightforward.“Ultimately, my physique, skill set, experience and height were all reasons I was chosen for the job,” Dalton told The Indian Express. “Beyond the physical match, they needed someone who could handle the performance demands and stunt work.”Her casting offers a glimpse into a part of filmmaking designed to go unnoticed. How closely does a stunt double actually need to resemble the actor? When can a woman double a man? And what allows filmmakers to swap one performer for another without audiences noticing?Dalton compared the process to putting together a puzzle: height and build matter, but so do movement, experience and the specific skills a sequence demands. Devyn Dalton is 4’6” tall, while Matt Damon is a fairly average 5’10”. Her smaller stature was in fact part of the point. Photo: Instagram“You might look exactly like someone, but if the job requires a particular fight style, a high fall, wire work or another specialist skill you don’t have, being their doppelgänger isn’t going to help much!” Dalton told The Indian Express.Story continues below this adMovement can be just as important as appearance. “Everyone walks, runs, stands and reacts differently. A good double learns those details and adapts their own movement so that everything feels like one continuous performance,” she added. Also in Explained | Never read The Odyssey? Here’s what you need to know before watching the new filmDalton’s own background spans dance, acting, motion capture and stunts. She said this has involved “studying movement and learning how to physically become different characters”.So when can a woman double a man?According to Dalton, stunt casting comes down to who is right for the job, even if women doubling for men is “definitely less common”.“We also have incredible hair, makeup and costume departments that can transform performers into whoever they need to be. I’ve spent a lot of my career becoming things I’m very much not in real life, so transforming into a man isn’t actually the strangest thing I’ve done!” Dalton said.Story continues below this ad“Ultimately, if you physically fit the role, have the right skill set and can safely deliver the performance, that’s what matters.” Adult stuntwomen have doubled young male actors: Emily Brobst (R), who is 4’10”, doubled Chandler Riggs, who played Carl Grimes as a teenager in The Walking Dead.Cross-gender doubling itself is hardly unprecedented. Adult stuntwomen have, for instance, doubled young male actors: Emily Brobst, who is 4’10”, doubled Chandler Riggs, who played Carl Grimes as a teenager in The Walking Dead.Cross-gender doubling has historically worked the other way around too. In Hollywood, male stunt performers would sometimes don wigs and women’s clothing to double actresses, a practice known as “wigging”. It eventually drew criticism from stuntwomen who argued that they were losing work to male performers. In 2018, US performers’ union SAG-AFTRA raised concerns about the practice while issuing new standards for stunt coordinators.India had its own version of this history. When pioneering stuntwoman Reshma Pathan entered Hindi cinema in 1968, male stunt performers were still doubling female stars, she told The Indian Express in 2019. Pathan was among the women who began changing that; several more female stunt performers entered the industry soon afterwards.So why don’t we notice the switch?Story continues below this ad“People tend to think you need to be the actor’s identical twin, but filmmaking has a lot more tricks up its sleeve than that,” Dalton said. What audiences often pick up on instead is body language: “how someone stands, their posture, rhythm and the way they move.”Research from the University of California, Berkeley, suggests yet another factor at play. In a 2014 study, researchers Alina Liberman and David Whitney found that our perception of a face is influenced by similar faces seen in the preceding several seconds, helping the brain maintain a stable sense of identity even as appearances change.“Our visual system loses sensitivity to stunt doubles in movies, but that’s a small price to pay for perceiving our spouse’s identity as stable,” Whitney said when the study was published.Story continues below this adThe illusion begins well before the cameras roll. Stunt doubles spend a lot of time rehearsing a sequence, working out the mechanics of a stunt and helping train actors for the action beats they will perform themselves. “You’re both working toward the same performance,” Dalton said.NewsletterFollow our daily newsletter so you never miss anything important. On Wednesday, we answer readers' questions.SubscribeMaking sure the audience never sees the switch is then a team effort, involving the stunt and camera departments, the director and editors, as well as costume, hair and make-up.“I’ve doubled children, creatures and now a leading Hollywood man, so clearly my face hasn’t been doing all the heavy lifting!” Dalton said.In the Laestrygonians sequence, Dalton’s height presented a different kind of advantage. Smaller stunt performers helped exaggerate the difference in scale between Odysseus’s men and the cannibals. Forced perspective can create such differences in apparent scale by manipulating the positions and distances of subjects relative to the camera.Story continues below this adFor Dalton, the attention around The Odyssey has helped challenge one of the biggest misconceptions about her profession: that stunt doubling is simply about looking like an actor.“In reality, it’s a highly technical profession combining athletic ability, acting, timing, precision and safety. There can be an enormous amount of preparation behind a few seconds of action on screen,” she said.“Stunt performers are storytellers. Sometimes we tell the story through dialogue, sometimes through movement, and sometimes by getting thrown across a room. It’s all part of bringing the character to life.”