JTBC's K-drama poster doubles as a drug-test kit — Gangnam crime drops 57.4%

JTBC was launching 'Strong Girl Nam-soon', a superhero drama about three generations of women taking down a Gangnam drug cartel, just as Seoul faced a surge in drink-spiking assaults — more than 8,000 cases of sexual assault using spiked drinks had been reported in three years.

Make the drama's promotional poster itself a functional narcotics test: 27 detachable strips that turn green within a minute if a drink is spiked.

Cheil printed the outdoor poster on real reagent paper so each of the 27 perforated round kits can test a suspicious drink: peel, drip, and the strip turns green if drugged. Posters went up around Gangnam subway stations, bus shelters, cinemas, cram schools, cafes, plastic-surgery clinics and pharmacies, and 800 copies were distributed, including to 20 Seoul universities. Printing took two months of trial and error — heat destroyed the reagent until the team shrank the poster, matched its colour to the reagent and left that area unprinted.

The kits were stripped off the posters within weeks: all 800 copies ran out and clinics and cinemas asked for more, with JoongAng Ilbo reporting the posters had become scarce. The LIA award entry says Seoul's drug-crime rate dropped 57.4% after the campaign. It won ADFEST 2024 Gold in Direct plus Silvers in Media and Outdoor, and a Bronze at LIA 2024.

In late 2023, South Korea was gripped by a visible rise in drug crimes, and the specific fear was drink-spiking: colourless, odourless, tasteless drugs such as GHB slipped into drinks, most often to enable sexual assault. More than 8,000 such assaults had been reported over the previous three years. Meanwhile JTBC was about to premiere 'Strong Girl Nam-soon', a superhero K-drama about a mother-daughter trio born with superhuman strength who take on a drug cartel in Gangnam.

Cheil Worldwide's art director Kim Kang-min connected the two: why not make the drama's promotional poster itself a drug test? Each poster was printed on real reagent paper, carrying 27 detachable round test kits. Users peel one off, place a drop of a suspicious drink on the strip, and within a minute the reagent turns green if the drink is drugged.

The production was the hard part. Two months of searching were needed to find a printer willing to risk it, because the heat of printing could destroy the reagent. The fix was to shrink the poster, print it in an apricot tone close to the reagent's colour, and leave the reagent area free of ink. Posters then went up around Gangnam — subway stations, bus shelters, cinemas, cram schools, cafes, plastic-surgery clinics and pharmacies — and 800 were distributed, including to 20 Seoul universities.

The public response was explosive. People stripped the test kits off the posters, all 800 copies ran out, and cinemas and clinics asked for more. JoongAng Ilbo ran the story under a headline calling the posters a sensation. The LIA award entry reports that Seoul's drug-crime rate fell 57.4% after the campaign, and the work swept ADFEST 2024 — Gold in Direct plus Silvers in Media and Outdoor — and took Bronze at LIA 2024.

It merged promotion with utility: the ad itself became a tool people wanted to tear off and use, not just look at.

The placement was inherently earned media — a poster that tests drinks is a story worth reporting on its own.

It matched the product's fiction (a superhero drama about a drug cartel) with a real-world civic problem, giving the drama relevance beyond entertainment.

The scarcity mechanic — kits being stripped from posters — turned distribution into proof of demand.

Let the media be the message: when a poster is also a functioning safety tool, the placement itself becomes the news, and the campaign distributes itself through word of mouth and public demand.

The campaign's impact outlived the drama's run. It became a reference case for functional out-of-home advertising in Korea and internationally, winning at ADFEST 2024 and LIA 2024, and coverage of the drop in Seoul's drug-crime rate kept the story circulating months later. The format — a media placement that does real work — was widely copied in civic and entertainment campaigns across Asia.