In 1998, a Japanese man who went by the nickname Nasubi was subjected to possibly the cruellest and most horrifying treatment in reality television history. The popular entertainment programme Denpa Shōnen would routinely feature people undergoing a variety of extreme challenges for the amusement of a television audience – but this one reached another level of horror. One “lucky” participant was required to spend an extended amount of time in a single room, alone.

He was to be stripped naked, and availed only with a pen and paper, and a collection of local magazines, each of which contained competitions. If he wanted to eat, or drink, or wear clothes again, he would have to enter these competitions, and hope to win. The ultimate aim of the game was to scoop prizes worth a value of ¥1m (£6,000).

Only then could he leave the room. The contestant, a hopeful young comedian called Tomoaki Hamatsu, 22, aka Nasubi, was randomly selected, then promptly sequestered. He would not see daylight again for 15 months.

“It wasn’t a happy process,” Nasubi says now, through his interpreter Eyre Kurasawa, in London’s Soho, a full 26 years later. “There was trauma.” Nasubi’s experiences predates both The Truman Show , the 1999 Hollywood film starring Jim Carrey in which a man unwittingly has his day-to-day life filmed and screened on television, and Big Brother , which in the early 2000s set the tone for reality TV’s boundless appetite for human denigration.

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