CNN  — 

“The Zone of Interest,” Jonathan Glazer’s Oscar-nominated historical drama, is technically a film about the Holocaust.

The film centers on the real-life Auschwitz commandant Rudolf Höss and his family, who live bucolic and seemingly mundane lives next door to the infamous concentration camp.

But viewers never see the unspeakable horrors taking place just on the other side of the garden wall. Instead, they hear them.

They hear them in the muffled screams, the heart-wrenching wails and the piercing gunshots. They hear them in the distant sounds of trains and in the constant hum of the incinerator.

“I knew right from the off that I didn’t want to reenact these atrocities using actors and extras,” director Glazer told CNN’s Christiane Amanpour in a February interview. “I feel that that imagery is something that we all know, and it’s seared into our consciousness as it is. Sound, of course, is interpretative. We’re able to see those pictures in our mind’s eye because we hear those sounds.”

In a film otherwise short on spectacle, the sound design in “The Zone of Interest” is something of a main character. (In interviews, Glazer has said “The Zone of Interest” consists of two films: “the one you see and the one you hear.”)

Those ambient noises are an ever-present, stomach-turning reminder of the evil that the Höss family is complicit in. They signal to audiences that Höss, his wife Hedwig and even their children are perfectly aware that millions of Jews and others are being murdered day in and day out — they’ve just managed to tune it out.

“In other words, it’s out of sight but never out of mind,” Glazer told Amanpour.

"The Zone of Interest"

Constructing a sonic depiction of the Holocaust, however, was no simple task.

Sound designer Johnnie Burn, whose work includes “Poor Things” and “Nope,” compiled 600 pages of research on the sounds that would have been heard at the extermination camp during World War II, IndieWire’s Sarah Shachat wrote in a piece titled “How ‘The Zone of Interest’ Uses Our Ears Like No Other Film.” That included everything from the planes, trains and automobiles of the era to survivor testimony describing what was going on inside the camp.

Burn has said in interviews that he spent a year gathering the audio that makes up the chilling undercurrent of the film. The effort required a great deal of creativity — rather than hiring performers to recreate the sounds of human suffering, he told IndieWire that he collected field recordings from places where one might hear such noises organically, such as the 2022 Parisian riots.

“No matter how good an actor is, faking the pain of a severe injury, of fatality, is a very hard thing,” Burn told IndieWire. “And the film itself has such a documentary, natural, realistic vibe that anything remotely wooden is not going to work.”

Burn also said in an interview on the Slate podcast “Working” that he recorded audio of voices from across various European cities to accurately portray all the nationalities that were represented at Auschwitz. To ensure that engine sounds were accurate to the time period, he sought help from a man in Estonia with a collection of World War II-era German motorbikes.

Another challenge that Burn and his team contended with was figuring out how discernible the sounds of Auschwitz would have been in real life. At the urging of the film’s production designer, he eventually amped up the aural intensity.

“It was an enormous amount of people and stuff coming and going every day, and I think (Glazer) and I knew that and we’d done our research, but somehow, I don’t know, maybe it [felt] disrespectful, but we were too gingerly applying the sound and so we went away and we put a lot more in,” Burn told IndieWire.

The resulting soundscape is perhaps the most disturbing aspect of the film. And while the film has earned some criticism for its indirect treatment of the Holocaust, Burn’s sonic feat has garnered him industry acclaim — “The Zone of Interest” won the BAFTA Award for Best Sound, as well as the top prize at the London Critics’ Circle awards. It also notched five Oscar nominations, including for Best Sound and Best Picture.

While “The Zone of Interest” is, on the surface, a movie about the Holocaust, Glazer and producer James Wilson have said its message remains urgent as ever. “It seems stark right now that we should care about innocent people being killed in Gaza or Yemen,” Wilson said at the BAFTAs. “In the same way [we] think about innocent people killed in Mariupol or in Israel.”

“That wall is a manifestation for me of how we compartmentalize the suffering of others — and normalize the suffering of others, to some extent — in order to protect and preserve our own comfort and security,” Glazer told CNN.

At its core, Glazer says, “The Zone of Interest” is about what we choose to pay attention to — and what we’re able to ignore.

“It’s not saying, ‘Look at what they did,’” he said. “It’s saying, ‘Look at what we do.’”