In each of the photographs in Unmarked his camera focuses on the precise spot the victim was found, and as viewers we are caught between the exquisite landscape and the trauma inscribed therein. The knowledge of what happened changes everything. Recently, Chalmers returned to the sites to collect flowers and grasses, which he has been drying and pressing in the basement of his home outside Youngstown, Ohio. He plans to include the cuttings with a limited-edition book of Unmarked that will be published this year, to strengthen the sense of connection to the places he has photographed. They are almost certain to become collectors’ items, and not just among the art-loving audiences he is hoping to reach.

Catharsis

One of the more provocative explanations for the appeal of serial killers is that they serve some kind of social function, allowing us to indulge our most vengeful fantasies without having to act them out, and, once the killer is caught, without having to feel guilty about it. “They’re almost like a catharsis for the worst of us, a lightning rod for our darkest thoughts, like the sin-eaters in medieval times who would take away the sins of others and by so doing cleanse society,” says Bonn. They also give us the opportunity to suffer death from a distance, to get “as close to the abyss as you can while not falling in”, as McCorristine puts it. This, he says, is why some people are compelled to watch Isis execution videos, even though they may later regret it. It could also explain why we slow our cars in the aftermath of a traffic accident, gawking for a glimpse of horror on the other side of the barrier.

Perhaps what we like most of all is to be terrified. I stand guilty. In 1995, I dated a girl in Paris who was convinced she was being stalked by a serial killer. The police seemed worried too. They thought her stalker could be the same man who had raped and stabbed to death four young women in her part of Paris over the previous 18 months. The police gave her an emergency phone which she could call any time, and a friend gave her a gun which she kept under her bed. She was terrified all the time. Frequently she refused to let me in fearing it was her stalker at the door. It terrified me too. But I was also transfixed, and addicted. Not that I told her.

Eventually the threat subsided. Three years later, the police arrested a man who confessed to the four mid-90s murders, and to three others. His name is Guy Georges, now known as the 'Beast of the Bastille'. He is serving life imprisonment with little possibility of parole. I have no desire to write to him, nor to solicit him for a painting or lock of hair. But I will probably watch L’Affair SK1, a film based on his story that came out this year. He will certainly be hard to forget.

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