hn ▁J ai - h ong ) ▁hon ed ▁his ▁director ial ▁skills ▁as ▁an ▁assistant ▁director ▁under ▁Kim ▁Ki - du k . ▁His ▁debut ▁film ▁R ough ▁C ut ▁( 2 0 0 8 ), ▁about ▁a ▁gang ster ▁who ▁wants ▁to ▁become ▁an ▁actor ▁and ▁an ▁actor ▁who ▁thinks ▁he ▁is ▁as ▁t ough ▁as ▁a ▁gang ster , ▁was ▁written ▁and ▁produced ▁by ▁Kim . ▁R ough ▁C ut ▁was ▁much ▁more ▁commer cially ▁orient ed ▁than ▁Kim ' s ▁own ▁mov ies , ▁and ▁the ▁star ▁power ▁of ▁its ▁two ▁leading ▁actors ▁So ▁Ji - sub ▁and ▁K ang ▁Ji - h wan ▁prop elled ▁the ▁ind ie ▁to ▁more ▁than ▁one ▁million ▁adm issions , ▁resulting ▁in ▁a ▁profit ▁ 1 0 ▁times ▁its ▁low ▁budget . ▁▁ ▁J ang ' s ▁second ▁feature , ▁Secret ▁Re union ▁( 2 0 1 0 ), ▁benef ited ▁even ▁more ▁from ▁the ▁director ' s ▁popul ist ▁sens ibility . ▁A ▁story ▁about ▁two ▁intelligence ▁agents , ▁one ▁from ▁South ▁Korea ▁and ▁the ▁other ▁from ▁the ▁North ▁( play ed ▁by ▁Song ▁K ang - ho ▁and ▁K ang ▁D ong - won , ▁respectively ), ▁who ▁approach ▁each ▁other ▁in ▁acts ▁of ▁esp ion age ▁only ▁to ▁develop ▁an ▁unlikely ▁friendship , ▁the ▁film ▁sold ▁ 5 . 5 ▁million ▁tick ets , ▁making ▁it ▁the ▁second ▁highest ▁gross ing ▁Korean ▁film ▁of ▁that ▁year . ▁ ▁His ▁third ▁film ▁The ▁Front ▁Line ▁was ▁a ▁large - scale