Director Danny Boyle is still shaken by the unforeseen complication he encountered during the production of his latest film, 28 Years Later. In an exclusive interview with PEOPLE, Boyle revealed that the intimacy coordinator's guidelines caught him off guard, leading to a "nightmare" situation.

The post-apocalyptic thriller follows a group of survivalists living amongst those infected by the Rage virus. Boyle explained that, in the context of the story, it would be realistic for the infected to be naked, as their clothes would have disintegrated over time. However, the presence of a 12-year-old boy on set, who played the key role of Spike, meant that no one was allowed to be fully naked on set under the Child Sex Offenses Act.

"We never knew that going in, it was a nightmare," Boyle said. "Interestingly, because there was a 12-year-old boy on set, you're not allowed for anybody to be naked, not really naked, so they look naked, but it's all prosthetics."

Boyle revealed that he had to make everybody prosthetic genitals, as a result. The director also discussed his experience working on the film, which is the third installment in the zombie-apocalypse franchise, following 28 Days Later and 28 Weeks Later.

28 Years Later hits theaters on June 20. For more entertainment news, check out the following articles:

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