The upcoming film, 28 Years Later, from Sony, is not only reviving the series’ post-apocalyptic world but also introducing new terrifying elements to the story.

In a recent interview with IGN, director Danny Boyle revealed that the Infected have developed new characteristics since their last appearance in 28 Weeks Later. In addition to the fast-moving Infected featured in the marketing, some have undergone a transformation to survive in their new environment, resulting in the emergence of “Slow-lows.” These slow-moving Infected “hang about low level” and are not prone to running. Despite their slow pace, Boyle cautioned against underestimating them, stating, “[I] wouldn’t advise messing with them.”

For fans of zombie video games, it’s no surprise that a single variant is rarely the only one lurking in the shadows. Alongside the Slow-lows, 28 Years Later will introduce Beserker and Alpha types, which are more powerful than the regular Infected and may possess some vestiges of intelligence amidst their Rage Virus-addled minds. From a technical standpoint, Boyle mentioned that the team shot the Infected “in a brittle, almost unreliable way,” similar to the approach taken in the first film. However, the new undead have been given additional flourishes, such as attaching cameras to Slow-low actors to amplify fear or utilizing 20 iPhones to record specific sequences simultaneously, creating a “poor man’s bullet time” effect.

The new Infected also influence the photography in 28 Years Later. Boyle shared with IGN that the film was shot in widescreen format to recreate the unease and visceral feel of the first movie. He explained, “If you’re on a widescreen format, they could be anywhere… you have to keep scanning, looking around for them, really.”

28 Years Later is set to hit theaters on June 20.

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