We were sitting at a kitchen table at his mom’s place when David told me about his first bushfire. It was nearly 30 years earlier, but he could still clearly remember lighting it.

This article is a longform version of the latest episode of our podcast "Extremes." To hear the actual interview, check out Extremes on Apple , Spotify , or wherever you get your podcasts.

For a long while, I’d been obsessed with the question of who deliberately lights bushfires. To me, the question became important in February 2009, after the Victoria Black Saturday bushfires in Australia destroyed large swathes of my home state and killed 173 people. Not long after, a 39-year-old guy named Brendan Sokaluk was arrested under suspicion for lighting one of the day’s biggest fires. Sokaluk eventually received 17 years in prison for 10 counts of arson—one for each of the 10 people who died in his fire.

It took the rest of the day to get the blaze contained. Later, when the job was done, the captain put a big meaty hand on David’s shoulder and said “you did well,” which was feedback he’d always wanted but never received. And in that moment, David decided he’d do anything to feel valued like that again.

“When I left, the area that was burning wouldn't have been any bigger than this table,” he said, motioning to the kitchen table. “But a few hours later it was several feet long.”

From there, David headed to the fire station where he worked as a volunteer and spent the next 10 minutes opening the roller doors and getting the trucks started. By the time the town’s sirens went off, he was ready to go. The rest of the crew arrived a few minutes later and they climbed into the trucks and headed for the national park, back the way David had just come.

“I just threw some matches on the ground,” he said. “I had a packet of Redhead matches and I used half the box just flicking them around. I waited until there was flame, and then I drove away.”

For this reason, I made it my personal mission to find a convicted arsonist who’d talk, so in early 2015, I began poring through old court documents looking for names. Once I’d compiled a list, I used social media to track people down and ask for interviews. For about a year I received nothing but refusals and ghostings, until one day I got a text from the guy I’m calling “David” in this story. He told me he’d been arrested for lighting bushfires as a teen, back in the late 80s, and if I wanted to know more I could come visit him at home.

Most newspaper reports included just a location and a description of the fire. If anyone was taken in for questioning, their names usually got withheld. Most importantly though, arsonists almost never spoke to the media, and in the one or two times they did, it was only to deny lighting fires. And so my question—who lights bushfires?—remained unanswered.

In the years since, words like “firebug” and “pyromania” routinely caught my eye. The idea that someone would deliberately light a fire on a gusty afternoon, then drive away and let their fire arbitrarily kill dozens—that idea seemed incomprehensible. And so I spent years looking for news stories that might provide a window into the psychology of arson, without much luck.

After that, my friend’s family left the state and moved to Perth. Like many, they decided there was too much heartbreak in Victoria.

I personally knew people who’d escaped that fire. Chief among them were my friend’s parents who survived by wading into a farm dam as the blaze roared over their home. I remember hearing how they’d stood in the water up to their necks, watching as their home’s LPG gas tanks exploded in the heat, blasting holes through the roof.

These findings were pulled from a total of 280,000 fires over five years. So even if we assume that less than half are deliberate, that’s still a large number of people lighting fires—and a pretty scary portrait of faceless lunacy around the country.

According to data, lots of people in Australia are drawn to destruction. One study produced by the Australian Institute of Criminology found some 13 percent of all forest fires are classified as “deliberate.” But as arsonists rarely get caught, a further 37 percent of fires remain “suspicious,” meaning it’s statistically likely that arson is the single greatest cause of bushfires in Australia. As the study notes: “for all vegetation fires for which there is a cause recorded, 50 percent may be lit deliberately.”

Australia is home to the most flammable landscapes in the world. California's scrub-filled canyons are also primed for fire, but not to the same degree. Here, our forests are dominated by Eucalyptus trees, which for tens of thousands of years have relied on wildfire to aid in seed germination, and have encouraged fires by filling their leaves with volatile oils. Of course, modern society puts a lot of effort into suppressing fire, but Australia’s ecology hasn’t changed. Our summers are still hot and dry; the flora remains highly flammable, and these factors provide an opportunity for anyone drawn to waging relatively effort-free destruction.

David explained that he lived with his mom, who’d gone out for the day to give us some space. He acknowledged it wasn’t cool to live with his mom, but admitted they both needed the company, and then I followed him into a house filled with family portraits and porcelain knick-knacks. Looking around, I got the feeling David’s life had moved pretty slowly since his adolescence.

I won’t reveal where David lived, as this was a condition of our interview, but I will say he lived in a Victorian weatherboard with a row of lavender out the front. I pulled up along the nature strip and David appeared on the porch, waving enthusiastically. He was a bit over 5ft, with sandy hair, and a grin that made me think of children on Christmas cards. He was in his late 40s but seemed young—not in a creepy way, but in a way that made me want to make sure he’d had enough for breakfast. I watched him bound over to the car with an outstretched hand. His orthopedic shoes clumped across the lawn as he ran, and I thought: H__e isn’t what I imagined.

This article is a longform version of the latest episode of our podcast "Extremes." To hear the actual interview, please subscribe to Extremes on Apple , Spotify or wherever you get your podcasts.

These days, thanks to research after Black Saturday, the criminal profile for bushfire arson is fairly well defined, but to my way of thinking, unsatisfyingly clinical. We know arsonists are usually men at an average age of 26, with a disconcerting number volunteering with the country’s fire fighting agencies. They also tend to be disconnected from friends and family and live with depression or mental illness .

We sat down at the kitchen table and David began to talk. He’d been a happy kid, growing up along the southeast coast with a family of sisters and loving parents. He described himself as outgoing and optimistic—until the age of 12 when everything changed.

“That was when I had a major event happen," he explained carefully, looking at the ceiling. “I was raped by my best friend.”

Without prompting, David told me the story of going to the beach with two older boys, one of whom pinned him down while the other raped him.

David became a different person after that. He didn’t tell anyone what happened, he just spent lots of time in his bedroom, plotting revenge and watching TV. He says his mom knew something was up and tried to talk but he brushed her off. The only thing that finally cut through was his dad signing him up as a junior firefighter, which gave him a distraction. Sexual assault had made him feel worthless, but working with the fire crew gave him a purpose.

“I suddenly felt I was being part of the community,” he said. “I’d help with fundraising, go down the street and jiggle the buckets. It gave me a sense of belonging I suppose.”