Synopsis: In this special series, The Straits Times dives into some of the greatest unsolved mysteries in South-east Asia, and examines the underlying issues that they exposed. In this episode, we revisit the spate of mass hysteria in Malaysia's north-eastern state of Kelantan to find out why the disorder is more prevalent among schoolgirls. ST regional correspondent Jia Ning Tan speaks to Ustaz Abd Rashid Ahmad, faith healer and spokesman of an Islamic medical facility called Darussyifa, and Mr Robert Bartholomew, a medical sociologist and co-author of Mass Hysteria in Schools: A Worldwide History Since 1566. She also interviews a woman who had a brush with mass hysteria as a schoolgirl and wants to be identified only as Nur. Highlights (click/tap above): (Headphones recommended) 1:53 The Ketereh Secondary School in Kelantan gripped by a fast-spreading screaming plague in July 2018 3:31 Students say they saw a tall, dark figure in the school compound 4:57 Ustaz Abdul Rashid Ahmad s...