In January 2018, Theresa May, then the prime minister of the United Kingdom, made an unusual appointment: Tracey Crouch would serve as the world’s first minister for loneliness. The position, May said, would address the fact that, for an estimated 9 million U.K. citizens, “loneliness is the sad reality of modern life.”

At the time, Alice Aedy, a British filmmaker in her 20s, was disconcerted by the news. “The idea of a minister for loneliness sounded very dystopian—almost Orwellian,” Aedy told me. “I thought it was a disturbing reflection of the times.”

The loneliness epidemic—as many experts are calling it—is a veritable public-health crisis. Research has shown that loneliness and social isolation can be as damaging to physical health as smoking 15 cigarettes a day. A lack of social relationships is an enormous risk factor for death, increasing the likelihood of mortality by 26 percent. A major study found that, when compared with people with weak social ties, people who enjoyed meaningful relationships were 50 percent more likely to survive over time.

John Cacioppo, who was a neuroscience professor at the University of Chicago and, until his death two years ago, the world’s leading expert on loneliness, discovered the deleterious effects of social isolation at the cellular level. “We found that loneliness somehow penetrated the deepest recesses of the cell to alter the way genes were being expressed,” he wrote in his book Loneliness: Human Nature and the Need for Social Connection.

These are alarming findings, considering that nearly half of Americans report feeling lonely most of the time. The problem is especially acute among young adults ages 18 to 22—a conclusion that is consistent among surveys conducted in the U.K., New Zealand, Australia, and Japan.

Why is Generation Z so lonely? It’s a question Aedy explores in her short documentary Disconnected, premiering on The Atlantic today.

Following the announcement of Crouch’s appointment, Aedy set up a hotline for young people interested in contacting the new minister for loneliness. Within 24 hours, the mailbox was full. “Nothing could prepare us for how emotive the voicemails were,” Aedy said. “On the first night we received them, we stayed up until 3 a.m. listening, sometimes in tears.” Many callers ended their message by thanking the listener for the opportunity to share their feelings, which they said provided a sense of catharsis.

A selection of these voicemails is heard in Disconnected. The testimonies are intimate and disarmingly honest. “It would have been difficult to get such revealing interviews in person or on camera,” Aedy said. It’s comforting to call an anonymous hotline, where “no one is there to respond or judge—as if you were stepping into a confession box.”

One caller describes his experience of being alienated in a large city. “I sit in my flat and watch people walk by and think, How am I so alone in a place with so many people?”

“Everyone else is having the time of their lives,” another caller says, “and you’re the anomaly.”

Audio of the calls plays over haunting, atmospheric imagery of people navigating what appears to be a sci-fi dystopia. In fact, the 16-mm cinematography was shot in Lancashire, a “loneliness hot spot” in England. “There’s a lot going on in the voice messages,” Aedy explained, “so we didn’t want the visuals to be over-prescriptive. I wanted to reflect the mood I had personally experienced when listening to the voicemails.”

As for the question she originally set out to answer, Aedy found that most of the anonymous callers referenced the strange dichotomy of feeling alone while surrounded by people. “This reinforced the notion that loneliness has little to do with being physically isolated, but more about a sense of disconnection from the people around you,” Aedy said.

Cacioppo, the loneliness expert, believed that social media can create a profound sense of estrangement. He wrote that internet communication is a kind of ersatz intimacy: “Surrogates can never make up completely for the absence of the real thing.”

After making Disconnected, Aedy agrees. “The fundamental promise of the internet—better human connection—has failed,” she said. “While we may technically be more connected, I think we are actually more isolated from each other than we have ever been.”