I'm not quite sure how it happened, but by coincidence, I ended up watching two Asian films about the underground organ-harvesting trade in one day. This is the one I knew covered that information, and it's the one I liked less, albeit slightly less; while there's a lot of good material here, and it's all well-presented, you're not going to find anything here you haven't seen before, probably many times.
Hyun-min Lee (The Legend of the Shadowless Sword's Hyun-jun Shin) is Korea's premiere facial reconstruction artist, but he quit his job recently in order to move to the country with his daughter, who has a congenital heart defect and is not expected to live longer without a transplant. She's currently off living with Grandma while he finishes cutting his ties with the institute where he works (where are all these jobs where people beg you to stay when you quit? I see them in movies all the time, but in real life, not so much...), but on the day before he's supposed to leave, Sun-yeong Jeong (Arang's Yun-ah Song), an up-and-coming university student whose greatest desire is to study under him, turns up with a box containing a skull. He refuses her, but she will only take a conditional no for an answer; she tells him she's leaving the box with him overnight and will be back to pick it up the next day. Cue haunting. When she comes back, the skull is out and mounted, though he has no memory of doing it, and so he reluctantly starts the process, both figuring out who belongs to this skull and mentoring Sun-yeong in the process. Meanwhile, other bodies are being discovered, and the ghosts haunting Hyun-min seem to be trying to point him to the killer.
Peiseu is a movie that's trying to be a little too much at once, I think. There's the obvious romance angle, there's the police procedural/mystery angle, there's the creepy-long-haired-ghost angle. Any two of those together would probably have worked well, but the material feels stretched a little thin, and it's likely you'll see the Big Twist(TM) coming a mile away. But it's all quite stylish and easy on the eyes; it's not an hour and a half you'll find yourself regretting, though you may want to just watch some of the other movies that did it just as well the first time around. ** 1/2