Move over, Sean Baker and Steven Soderbergh—Danny Boyle is the latest director to make the bold choice to shoot his latest feature film on an iPhone. Why, you ask? Partly, perhaps, because the team knows it will get them some nice headlines like this one. And partly just because they can.

Whether you love or hate the idea of shooting professional video on iPhones, it’s hard to argue that these latest smartphones aren’t capable of high-end video.

The iPhone 15, which is what Boyle and his team reportedly used for the long-awaited follow-up to the original 28 Days Later in 2002 and its 2007 sequel 28 Weeks Later, in particular, has proven to be a major step forward for Apple and was very much promoted as a filmmaking-capable camera.

Still, as is always the case with these smartphone-shot feature films, there’s more to the story than just the headline here. So let’s explore how Danny Boyle and his team were able to shoot 28 Years Later on an iPhone.