The ever-busy K-pop veteran takes on his first lead in 14 years — a Korean-Japanese horror flick he is still trying to decode Kim Jae-joong (Library Company) "When you sign onto a cross-border project like this, that's bait you can't resist," Kim Jae-joong says of "The Shrine: Whispers of the Evil Spirit." "I figured something would come out of it that you couldn't get any other way."The man across the table at a cafe in central Seoul on Tuesday has been a fixture of the Korean entertainment landscape for so long, it's easy to forget how many lives he's lived inside it. He broke through in 2003 with TVXQ, broke away to form JYJ, then went solo across Korea and Japan. At 40, he's something close to the industry's elder statesman — though he'd wave the title off. There's always a "seonbae" (senior) above him, he insists.He's been trying his hand at all sorts of things lately. Away from the music, Kim turns up regularly on "Stars' Top Recipe at Fun-staurant," a cooking-variety show where celebrities pitch dishes to a panel of food-industry buyers; his run on it won an Excellence Award at last year's KBS Entertainment Awards. He also runs his own management agency, looking after the K-pop acts on its roster."The first job is to make them work commercially," Kim says of his artists. "Their futures, their livelihoods — it's all tied to mine now. So you make them happy, they make audiences happy and round it goes."Acting, by comparison, has tended to take a back seat, which is exactly why "The Shrine" is something of an event. Directed by Kazuyoshi Kumakiri, a Japanese filmmaker known in the indie circuit, the Kobe-set horror flick is Kim's first feature lead since the largely forgotten 2012 action-comedy "Code Name: Jackal."The story sends Kim's shaman, Myung-jin, to Japan after three Korean students vanish at an abandoned shrine, where he squares off against a spirit that won't quite stay out of his body.At first glance, it sits squarely in the breed of occult thriller that "The Wailing" and "Exhuma" made a homegrown specialty — "mudang," or shamans, plying their trade against malevolent spirits, in feverish sword-dancing rituals that claim the living. Kim says it didn't feel that way from the inside."Going in, it felt completely new," he says. "The way they shot, all of it. And the back-and-forth with the director never stopped — we kept talking, kept working it out, even mid-shoot."New is one word for it indeed. "The Shrine" is no ordinary occult picture. It is, by most measures, a mind-bender — a film that throws its motifs in a blender and takes off, leaving you to sort out the mess. Call it an ecumenical fever dream, if you will: A pastor turns up in Catholic robes, a shaman chants Buddhist prayers and a Hindu demon is set loose in a Japanese shrine.Asked about the muddled iconography, Kim points to the director's design. Kumakiri wasn't after a traditional Korean shaman, he explains — he wanted a dark hero in a clean suit, the whole thing pushed toward fantasy. "He killed off all the standard shaman business," Kim says. "So he pulled in a bit of everything and packed it all into one figure." Kim Jae-joong stars in "The Shrine: Whispers of the Evil Spirit" (Library Company) At least some of the confusion seems to have been baked into the process itself. Kumakiri was decisive but improvisational, Kim says, willing to keep whatever came out differently if the feel was right — a rehearsed torso frame opened into a full shot, a take where his character wept off-script.Rarely does an interview with a star turn into a scene-by-scene defense of a movie, but more than once, Kim sounded like he was still working out the choices himself. "There are a lot of hidden mechanisms in this film," he says. "I'd hope people come out wanting to look closer. I was the same way making it."There's a more grounded register to Kim when the talk turns from the film to the long arc of his career. Two decades in, he doesn't see himself nearing anything like closure; the opposite, if anything."The longer you do this, the further you drift from anything like perfection," he says. "Solve one problem and a new one shows up. You start noticing more, you get stubborn about your own way of doing things."Then the talk turns to family. Much of Kim's recent TV fame has come from opening his family — a very big one, as it turns out — up to the cameras. He was adopted at 3 into a household of eight sisters, becoming the youngest child and the only boy. At last year's awards ceremony, upon accepting the prize, he credited his parents with nearly all of it. It all worked, he said, because the family's stories were real.Family looms large in his life — he has more than a dozen nephews now — and yet starting one of his own feels out of reach. He sees it as something most people work up to: get yourself sorted, find some footing, then build around others. He's not there yet."I'm not even close to that baseline," he says. "There's still too much responsibility to take care of. I need things to feel more settled before I can even start thinking about my own happiness."He took his parents on a vacation to Jeju Island not long ago and watched them get exhausted by the end of it. To him, that was proof that the window for doing things doesn't stay open forever."I don't want to look back and wish I'd done more," Kim says. "It's always better to just go for it while you still can.""The Shrine: Whispers of the Evil Spirit" opens June 17 at CGV theaters nationwide.