How Single's Inferno Is Made: Casting, Paradise Rules and the Island-Set Dispute

A dating-show fan and a deserted island

Single's Inferno (솔로지옥) premiered on Netflix on December 18, 2021, with two episodes a week over four weeks.¹⁹ It was made by two JTBC variety producers, Kim Jae-won (김재원), who had directed the channel's Traveller in Argentina, and Kim Na-hyun (김나현), with Kim Soo-ah (김수아) as chief producer.⁴ Kim Jae-won called himself a dating-show fan who watched every one on Korean TV, and said he made his own because the previous year had so few.³ He had once filmed on a deserted island and found it harsh but beautiful, so he entered "a dating show on a deserted island in midsummer" in an in-house JTBC pitch contest. The company told him it suited Netflix better.⁷ The Korean title is short for 솔로지옥, 커플천국: "singles' hell, couples' heaven".³

The first two seasons were shot on Saseungbong-do (사승봉도), a small island in Ongjin County, Incheon, by arrangement with the county and the island's owner.¹² The show is filmed in summer and released in winter, and Season 1 was finished in full before release. Kim Na-hyun said that gave her time for editing that a weekly TV show never had.⁵⁷¹⁴ Kim Jae-won has directed all five seasons. By Season 3 he and co-producer Kim Jung-hyun (김정현) were working under Shijak Company, the production company he founded in 2022, and Park Su-ji (박수지) was the third producer from Season 4.^1141922

The rules: Inferno and Paradise

The singles live on the island, the "Inferno", where electronics aren't allowed.²⁰ The only way off is as a couple. When two people pick each other they spend a night at "Paradise", a luxury hotel suite, and only there may they tell each other their ages and jobs.⁶ Kim Jae-won said the rules were built to keep the two places emotionally apart, because those left in Inferno often have to sit out a night while the person they like is in Paradise with someone else.⁸ The final pairs are made in the last episode.¹

There is no prize. Contestants get an appearance fee only, because the producers thought prize money would bring motives other than real feelings into play.⁷ The newcomers who arrive mid-season were planned in advance, and Kim Jae-won said Season 1's came late because the original cast needed two trips to Paradise to get to know each other.⁶⁷ In a studio, a panel watches the footage and reacts: model and TV host Hong Jin-kyung (홍진경), actress Lee Da-hee (이다희), Kyuhyun (규현) of Super Junior and rapper Hanhae (한해) from Season 1, joined from Season 3 by Dex (덱스), a Season 2 contestant.¹³¹³

Casting: DMs, referrals and street flyers

For Season 1 the producers searched Instagram for people who "work out", the keyword Kim Jae-won said would set the cast apart from other dating shows, and messaged them. They also took referrals and applications, asked companies and schools for recommendations and, when that ran dry, handed out flyers in the street.⁵⁷⁸ Kim Na-hyun said confidence was the first thing they looked for, and that they didn't insist on non-celebrities: people already on TV or YouTube were cast if they suited the show.³⁵ Women were the hardest to cast, the producers said, because many assumed it was a Korean version of Netflix's Too Hot to Handle.⁷

Everyone cast went through several interviews and Netflix's own vetting, and before filming each one saw a psychiatrist to check they could handle the stress of a reality show.⁵⁷ The producers said the checks continue during broadcast for anyone who's struggling.¹⁶ By Season 3, casting took three to four months, and the team was also writing to the PR departments of companies and public bodies; that's how a Korea Coast Guard officer came to be cast.¹⁴ After Season 1 drew questions about counterfeit luxury items worn on the show, which the producers said they hadn't known about, they began checking cast members' clothes.¹⁴ For Season 4 they interviewed more than 500 candidates and cast someone only when most of the team agreed. At least two of that season's singles were found by street casting.¹⁹²¹ Netflix says the producers compare casting to picking athletes for a national team.¹⁷

Editing: no script, few captions

Korean variety shows usually run about 90 minutes an episode with captions throughout. Single's Inferno aimed for about 60 minutes, captioned only to explain a rule or clarify hard-to-hear audio, and cut almost everything that wasn't about the romance, Kim Jae-won said, so that viewers abroad would find it easy to watch.⁵⁶ Asked whether there was a script, Kim Na-hyun said there "can't be" one in a dating show and that the crew's intervention on site was "close to zero"; the only request was that the singles express their feelings honestly.⁶

The editing rule has stayed the same: anything that bears on a love line goes in, and other remarks may be cut to protect the cast, Kim Jae-won said after Season 3, when some contestants' comments drew criticism.¹⁵ In Season 4 the producers said they cut "without hesitation" any moment when a contestant's sincerity wavered.²⁰ After Season 5, when some of the panel's remarks about a contestant were criticised, Kim said the panel's comments were "100% the producers' responsibility", since the producers had asked them to be frank, and that the next season would tone them down "by a spoonful".²³²⁴

The show's frankness was questioned from the start. In July 2022, a Netflix content manager, Yoo Ki-hwan, said Netflix didn't consider it sensational and that it set out to show young people's honest interactions.¹⁰

Changing the formula

Kim Jae-won said that, by Season 3, viewers knew the format, location and rules too well, so the goal was to change everything from Season 2.¹⁴ The singles were split between two Infernos. The first-night group dinner was dropped (he said global viewers couldn't see why the cast cooked instead of dating), so couples could leave for Paradise within 30 minutes of meeting. The camp, which had felt like glamping, was cut back to container boxes to push the cast to be more direct.¹³¹⁴ He acknowledged the season divided viewers: some missed the romance and found it more like a sitcom.¹⁴

For Season 4, Kim Jung-hyun said the team had regretted having no male catfish in Season 3.²⁸ At the end of episode 4, three candidates were revealed and the women picked one to stay; the other two went home.¹⁸ Kim Jae-won later called that "catfish survival" a failure.²⁵ Season 5 had 15 singles, the most in the series, and the producers compared it to the multi-strand film Love Actually: more lead characters, and less focus on one or two breakout stars.²³²⁷

The Season 3 set: what was disputed, and the answer

On May 31, 2023, the environmental group Incheon Green Korea United (인천녹색연합) said a set for an OTT entertainment shoot on Saseungbong-do was damaging its coastal dunes and threatening the habitat of a legally protected crab. It counted more than ten structures, including six container boxes. The island has been part of the marine protected area around Daeijakdo since 2003, where new buildings are banned except, with a permit, for military or research use, and the group said the company hadn't applied to Ongjin County for one. It asked the Ministry of Oceans and Fisheries, Incheon and the county to restore the site and punish those responsible.¹¹

Sports Kyunghyang later reported that this was Season 3 of Single's Inferno: unlike the first two seasons, which were filmed by agreement with the county and the owner, about ten temporary buildings had gone up without permission, and the production apologised in June 2023.¹² Asked about it in January 2024, Kim Jae-won said it happened "entirely because we didn't check carefully" and that the team would be more careful from then on.¹⁴ None of the articles opened for this post reports a fine or other penalty, or says where Season 3 was finally filmed.

The scorecard

Netflix says Season 1 was the first Korean unscripted series to make its global Top 10 for non-English TV.¹⁷ Netflix's Top 10 file shows every season since has made the list: Season 3 stayed for five weeks, from its first episode to its last, and Season 5 spent three weeks at No. 2, the show's best rank, with 45.1 million hours in the week ending February 8, 2026. Season 4's 23.1 million hours was the show's biggest opening week until Season 5's 23.6 million.²¹⁷ For how these runs compare with other Korean reality shows, see Korean Reality Shows in Netflix's Global Top 10.

Each renewal set a record for Netflix in Korea. Single's Inferno was its first Korean unscripted series renewed for a fourth season, then the first Korean reality series to reach a fifth.¹⁷²² On February 13, 2026, Netflix confirmed Season 6, the first unscripted title in Korea to get one.²⁶