"It didn't feel like I was reading fiction," Kim Min-ha says of the script for "Hana Korea." "It felt like reading someone's diary." She had her reasons. The film casts her as Hye-sun, a 21-year-old from North Korea's Ryanggang Province who defected to the South to pay her mother's medical bills back home. Her narrative is built around a series of letters she writes home in voice-over. Stories like Hye-sun's are hardly scarce on Korean screens, but they mostly belong to documentaries and talk sh