Even though professional, cinema-quality digital cameras are now commonplace, they’re generally not small or compact. (Take a look at Arri’s current lineup, for example, with its Mini LF, used to capture Deadpool & Wolverine.) However, Danny Boyle’s forthcoming zombie flick, 28 Years Later, was shot over the summer with a bunch of adapted iPhone 15s, WIRED has learned, making the Hollywood thriller, with its budget of $75 million, the biggest movie to date filmed with smartphones.

Starring Killing Eve‘s Jodie Comer, next James Bond favorite Aaron Taylor-Johnson, and Ralph Fiennes, 28 Years Later, due for release in June 2025, is the long-awaited follow-up to 28 Days Later—the 2002 genre-defining movie that was the first to portray zombies as scary fast rather than lumbering—and 2007’s 28 Weeks Later. Boyle is joined by cinematographer Anthony Dod Mantle; they won Oscars together in 2009 for their hit Slumdog Millionaire. Mantle was also cinematographer on the original 28 Days Later, as well as Boyle’s films Trance (2013), T2 Trainspotting (2017), and 127 Hours (2010).

There’s a tech story arc to Boyle and Mantle choosing Apple’s log-profile powerhouse for 28 Years Later: The pair’s 2002 kick-off movie, 28 Days Later, was filmed with an innovative-for-the-time digital camera—one of the first Hollywood feature films shot with a Canon XL-1. The lust-worthy $4,000 prosumer camcorder had interchangeable lenses and wrote data to MiniDV (digital video) tapes.

Principal filming for 28 Years Later wrapped at the end of August, and until now the production has kept under wraps the fact that the movie was shot with smartphones, with the film’s staff being asked to signed NDAs preventing the disclosure of this detail. But a clue has been online for some months: A single paparazzi photograph out of a portfolio of 150, shot in July, shows Comer standing close to a movie camera that, at first glance, appears to be a high-end model such as those made by German manufacturer Arri, a standard choice for professional cinematographers new and old.

But zooming in reveals that the long lens isn’t attached to a regular camera body or a high-end modular system such as the Achtel 9×7. Instead, it is connected to a protective cage holding something that could be an iPhone, a professional camera operator not involved with the movie told WIRED.

The use of Apple smartphones as the principal camera system on 28 Years Later was subsequently confirmed to WIRED by several people connected with the movie, detailing that the particular model used to shoot was the iPhone 15 Pro Max. (Evidently, filming took place too early for Boyle and Mantle to get their hands on the new iPhone 16 series.)

The iPhone in the paparazzi photo is held by an aluminum cage fitted with a lens attachment adapter. Beast makes such cages and adapters, adjusted with distinctive red knobs (there’s such an adjustment knob visible in the photograph), and its latest DOF (depth of field) adapter allows the attachment of full-frame DSLR lenses to smartphones. The lens-shaped adapter, released in March, projects the image from the DSLR lens onto the surface of its screen, and the smartphone records this projection.

Several arthouse films have been shot with iPhones, including Sean Baker’s Tangerine (2015) and the Steven Soderbergh drama Unsane (2018), but these movies were limited-release, low-budget offerings compared to 28 Years Later. The new film’s $75 million budget is only part of the franchise’s total, with 28 Years Later being the first of a new trilogy; all three coming zombie films are being scripted by screenwriter Alex Garland, who is reuniting with Boyle and Mantle after helming Civil War, released earlier this year.

Another key team member from the 2002 movie is back for at least one film in the new trilogy: Long before his razor-blades-in-flat-caps role in the gritty TV show Peaky Blinders—or his Oscar-winning, Bhagavad Gita–quoting performance in Oppenheimer (2023)—Cillian Murphy’s breakout role was as the lead actor in 28 Days Later. A full-frontal wide shot of him lying naked on a gurney was Murphy’s introduction to the limelight. (Murphy didn’t appear in the Boyle-produced 2007 sequel 28 Weeks Later. This movie, starring Robert Carlyle and Idris Elba, and directed by Juan Carlos Fresnadillo, was shot on film, and enjoys the same cult status as the first.)

There are no details yet on the plot for 28 Years Later, or whether Murphy stars in all three movies of the upcoming trilogy.

In the original movie, Murphy, then just 26, played Jim, a confused bicycle messenger waking from a coma in a deserted London hospital a month after being hit and injured in an unseen crash. In memorable scenes of a desolate London, Jim walks from the hospital and slowly discovers he’s one of the few not to have caught a virus that causes “infecteds” to feast on human flesh.

The highly contagious zombie-creating virus—billed as Rage, communicable through blood, taking hold within seconds—had been released into the wild 28 days before Jim’s crash, when anti-vivisection activists freed chimps from a top-secret primate research facility.

The crack-of-dawn scenes of an eerily quiet Rage-ravaged central London were tricky to film, as city officials in 2001 imposed strict time constraints on the moviemakers. Filming with bulky, unwieldy traditional film cameras would have taken ages to get the multiple tight angles required, so Boyle and Mantle took the huge risk of shooting with eight lightweight Canon digital camcorders—which, at that time, were classed as entry-level ENG (electronic news gathering) cameras, rather than as Hollywood-capable. Using the XL1 meant sacrificing high-quality film stock for relatively cold, low-resolution digital footage saved to MiniDV; fortuitously, the movie’s harsh look became intrinsic to 28 Days Later’s much-copied aesthetic.

But there was a downside to going digital: Unlike film, which can be upscaled for today’s high-definition screens, footage originally shot on DV tapes can’t be as easily remastered. This disparity is brought into literal sharp focus by the movie’s final scenes, which were shot on celluloid with an Arri camera for a distinctively dreamier look. After restoration, the part of the movie shot on film looks pristine, while the rest of it, shot on the Canon XL1, looks, well, digital.

Such a comparison is not easy to make now, as the film was withdrawn from streaming services in January when Disney lost the rights to the original movie. 28 Weeks Later, for which Disney still owns the rights, remains streamable. In a bidding war with Warner Bros., Sony acquired the right to finance the new trilogy, but the company has yet to reveal whether it will release a restored 28 Days Later.

The DV footage of the 2002 film was shot at standard definition (SD) of 480, lower than the 720 high-definition (HD) of other video cameras available at the time. In this day and age, where 4K is normal, even HD is considered blurry; however, the decision to shoot with the prosumer camcorder at a resolution of 480 on to MiniDV paid off, and Murphy’s bewildered walk through Westminster is still genuinely iconic.

“If I had shot those [scenes] on a big negative, it would have looked absolutely stunning,” Mantle told the magazine American Cinematographer in 2003. But he said it would have taken a fortnight to film instead of four days. “We would not have been allowed to shoot and take up so much space [required for shooting with film cameras] for two weeks at such a delicate time before early-morning rush hour,” Mantle stressed.

Andrew Macdonald, the producer of the original film as well as of the coming trilogy, said in 2002: “We were able to shoot for an hour or so before the city got too busy for us to hold back the traffic. When you see the whole of Westminster Bridge and the Embankment all closed for you, and the traffic stopped, and you can’t hear anything, it was thrilling.”

Placing a red double-decker bus on its side outside Downing Street hadn’t been okayed by authorities, but as no city officials turned up for the shoot that morning, the props team went ahead anyway.

Filming took place in July 2001, three weeks before the real-life horrors of 9/11. Moviemakers today likely wouldn’t get permission for such a mock-up in a highly security-sensitive location. Shot on a budget of $8 million, the movie was a sleeper hit worldwide, earning $84.6 million.

In addition to using the iPhone 15 Pro Max as the principal camera, some scenes in 28 Years Later were shot with action cams strapped to farm animals—what one might term “GoatPros,” then.

Boyle and Mantle were contacted for this piece but have yet to respond. WIRED understands that the producers of 28 Years Later looped in Apple before filming started, and that the Cupertino company provided technical assistance to the moviemakers.

The iPhone 15 Pro and Pro Max can shoot Apple ProRes video in log color profile at 4K resolution. ProRes is Apple’s video codec, released in 2007 and thereafter widely adopted by video and cinema professionals. Log (short for “logarithmic”) footage preserves more image information in the highlights and shadows, allowing for greater flexibility in the postproduction editing of colors, contrast, and highlights. Shooting at 60 fps in ProRes on an iPhone is data-hungry, so it is usually done with external storage.

Log files straight out of the iPhone 15, or any camera, look flat, with low contrast and saturation. The files must be edited in programs such as Adobe Premiere or DaVinci Resolve, where contrast and color tone are applied, achieving the desired saturation and overall look. Apple introduced the ability to shoot with the ProRes codec on the iPhone 12 Pro, but only the iPhone 15 Pro, the iPhone 15 Pro Max, and the new 16 can also shoot in log.

The second offering of the new Boyle/Garland trilogy—listed as 28 Years Later Part II: The Bone Temple—is currently shooting, and is being directed by The Marvels and Candyman director Nia DaCosta.

Any new Boyle film is almost guaranteed time in the critical spotlight, but by shooting this latest zombie flick on a high-end iPhone, the release of 28 Years Later in 2025 will also likely boost Apple’s cinematic street cred, too.