Copenhagen, Denmark — Peter Madsen, a self-taught engineer known for his unique inventions, once had a distinctive way of attracting attention, often asking women if they wanted to see his submarine. In 2008, Madsen built the UC3 Nautilus, claiming it as the largest amateur submarine globally, in a privately operated lab near Copenhagen. His unconventional pursuits extended to exploring the darker sides of social gatherings, often frequenting BDSM clubs, while being married.
Madsen’s fascination with submarines and exploration would ultimately lead to tragic consequences. On August 11, 2017, he invited Swedish journalist Kim Wall aboard the Nautilus for a short excursion, which turned into a nightmare. The 30-year-old Wall was later found to have been brutally murdered and dismembered by Madsen, who was 46 at the time of the crime.
In the aftermath, Wall’s remains surfaced over weeks along the shores near Køge Bay, shocking the public and raising questions about Madsen’s violent actions, especially given his previously unblemished history. Court documents revealed horrific details, including allegations of torture and sexual assault prior to Wall’s death.
Matthew Gavin Frank, in his new book “Submersed: Wonder, Obsession, and Murder in the World of Amateur Submarines,” explores the subculture surrounding amateur submarine enthusiasts and the psychological perils that may accompany such a fascination. He suggests that an obsession with underwater exploration might mask underlying psychological issues, posing a danger not only to individuals but also to those around them.
Amateur submarine builders often consider themselves part of a niche community, defined by a shared passion but also by their eccentricities. The PSUBS collective, a group dedicated to personal submersibles, gathers annually in Muskegon, Michigan. Many of its members, predominantly older men, express a certain distrust of authority and a desire for independence, finding solace in their underwater pursuits.
Among these enthusiasts is Hank Pronk from British Columbia, who constructed the Elementary 3000, recognized as the deepest-diving homemade submarine. Like many of his peers, Pronk learned the craft through DIY resources online, a testament to the community’s spirit of self-education and innovation.
Also notable in the community is Shanee Stopnitzky, who left her marine biology studies to pursue submarine innovation. She has created several submersibles, including one whimsically named “Fangtooth,” reflecting the light-hearted side of a hobby that can often traverse into more serious realms.
However, the allure of submarines also comes with a darker dimension. As Frank highlights, the merging of isolation and underwater fascination can lead to eccentric behaviors among enthusiasts. Some, like Albrecht Jotten in Alaska, have withdrawn from society entirely, viewing their submarine construction as a form of art, while believing they possess insight that could revolutionize naval engineering.
Madsen’s case particularly underscores the unsettling intersections of creativity, obsession, and violence. Experts in diving medicine have pointed out that the pressures experienced by those immersed in underwater activities can affect mental states, sometimes leading individuals to experience delusions or impulsive behavior.
When Madsen faced murder charges in 2018, his behavior in court raised eyebrows. He made bizarre comments about his interactions with women and likened himself to characters from popular films, raising questions about his mental clarity during the proceedings. Despite claiming a variety of explanations surrounding Wall’s death, his testimony was marked by contradictions and odd assertions.
Currently serving a life sentence at Herstedvester Prison, Madsen continues to harbor dreams of escape, revealing a persistent obsession with building and creating even within confinement. His story serves as a cautionary tale, illustrating how a seemingly innocuous passion can spiral into darkness, echoing the complex relationship between innovation and human morality.