The Contestant: a sobering look at one of the earliest and strangest chapters in reality TV history

As Hamatsu Tomoaki prepared to leave his Fukushima home and head to Tokyo in hopes of succeeding as a comedian, his parents gave him this advice: “Whatever you do, don’t get naked.” This may seem unusual. But in light of the events recounted in Clair Titley’s bracing and bizarre documentary, their words feel both prescient and astute about the ease with which humiliation is transformed into entertainment.

Even so, none of the Hamatsus could have imagined the ordeal that he would endure after being cast on Susunu! Denpa Shōnen, a TV show that became an instant hit in 1998 by presenting creatively sadistic competitions as the height of hilarity. Hamatsu’s task was to subsist entirely on winnings from magazine contests, a challenge that meant spending 15 months in a tiny apartment, naked, with only a camera for company. Miserable, malnourished and losing his mind, Hamatsu didn’t even know he was appearing on the show, let alone becoming its biggest star.

A look back at one of the earliest and strangest chapters in the history of reality TV, The Contestant is full of details that seem not just too weird to be true, but too cruel. That includes the decision by the show’s producers to give Hamatsu the nickname Nasubi (‘Aubergine’). A mean epithet referring to the shape of his face, it also gave the show its signature visual gag: an eggplant-shaped graphic used to obscure his genitals on screen – a possible origins story for a certain emoji.

A largely sober tone allows The Contestant to avoid the kitsch that the subject of Japan’s extreme brand of TV competitions typically attracts. It also makes the machinations of Tsuchiya Toshio, producer of Susunu! Denpa Shōnen – presented in new interviews alongside Hamatsu, former BBC Tokyo correspondent Juliet Hindell and other players in this true-life tragicomedy – seem all the more diabolical.

Indeed, the saga here has such an abundance of shocking and surprising turns, the film’s tight construction and modest runtime don’t leave much opportunity to delve more deeply into the questions arising from Hamatsu’s experience and how it anticipates equally sordid if less elaborate means of exploitation in the decades to come. (In the same year Nasubi became a phenomenon in Japan, Big Brother began to transform the medium on another side of the world.) The Contestant is also too reserved when it comes to the process by which Hamatsu recovered his sense of self. Then again, it’s understandable that Titley treads gently with her main subject – clearly the man has suffered enough.

► The Contestant arrives in UK cinemas 29 November.