Have Your Say: What's The Best Korean Film You've Ever Seen?

Until this spring, we used to reminisce about the "Korean Wave", that glorious age of cinema which started about twenty years ago (opinions differ), and which had yielded us so many great titles.
When the wave started, one thing which became notable about Korean films was that even the mediocre and bad ones often looked incredibly polished and full of style. A big difference with, say, mediocre and bad Japanese films, of which even the big-budgeted ones tend to look decidedly more lackluster on the visual front.
So for a while we gaped in awe at any Korean output. It didn't last, but while it did it was quite a ride, and for years we lamented such an age was unlikely to return soon...

...Until, as I said, this spring. Because this year, we encounter a kind of Korean Tsunami. The festival hype surrounding Na Hong-jin's fantastic The Wailing turned out to be just the start, as we've had the (legendary) Park Chan-wook's The Handmaiden, Yeon Sang-ho's zombie epic Train to Busan, and now Kim Jee-woon's The Age of Shadows (seen above). All four boast excellent production values, daring plots, and look sumptuous. Fingers crossed we'll get a few more!

Which brings us to the question of the week: what is the best Korean film you've ever seen?
Chime in, in the comments below, and HAVE YOUR SAY!