We meet the South Korean grandmothers going back to school, keeping classroom doors open in struggling rural towns.
They have been found everywhere – in bathrooms, subways, hotels, even schools.
Thousands of tiny cameras hidden across South Korea secretly record people’s most private moments, with the footage distributed online.
Arrests for “molka”, the Korean word for hidden camera, have soared in the last decade, with perpetrators coming from all corners of society – from a television anchor and a K-pop star to doctors.
Even teachers have confessed to hiding cameras in school bathrooms, filming children and colleagues.
101 East investigates how one of the most connected countries in the world is waging war against digital sex crimes.