Patrick Frater Asia Bureau ChiefLocal thriller “On The Line” held on to top spot at the South Korean box office charts. But its weak total showed that the boost to cinemas from the Chuseok holidays had been short-lived.“On the Line” managed $1.56 million in its second weekend, a score which was only 28% down on its debut, according to data from Kobis, the box office tracking service provided by the Korean Film Council (Kofic).