A nice epic historical drama, of the sort that Asians (in this case, South Koreans) seem to do so much better than we do. If you're up to reading subtitles for over two hours, and aren't averse to sorting out characters where everyone (sorry) kinda looks alike, check it out.
It's set in 17th-century Korea; the King, Gwang-hae, has a fine line to tread between contentious factions in his own country and the superior military power of China and Japan. He's extremely (and, it turns out, justifiably) paranoid about his personal safety.
Which leads him to assign his trusted advisors with a desperate task: to find a reasonable double, who can take his place in risky situations (like dinner, where the food could be poisoned). They find Ha-seon, a bawdy song-and-dance man employed at the local whorehouse. He's an obvious physical double, but nearly a polar opposite from the King in every other way: cowardly, impulsive, and, uh, not that smart.
But he gets hired, of course. (It helps that Ha-Seon doesn't really grasp what he's getting into, or his likely fate.) And there are some really funny bits as he gamely attempts to act royally.
But he grows in the role. When the King is mysteriously taken ill, everyone has no choice but to make the best of the situation. Surprising everyone, most of all himself, Ha-seon finds himself righting wrongs, fighting injustice, standing up for the nation: things that the King himself had failed to do. Which, of course, puts him in more danger.
It's also gorgeous. The men wear funny hats.