Writer-director Hong-jin Na has put together an epic, rather long South Korean horror film that keeps messing with your head nearly to the point where you just can’t take anymore.

A strange old man (Jun Kunimura) shows up in visions, and then is discovered in the flesh, in a small village where Jon-Goo, a hapless cop (Do Won Kwak), lives with his young daughter. Village residents start killing each other off and occasionally acting like zombies covered with strange boils. Then, Jon-Goo’s daughter starts exhibiting symptoms of possession, setting Jon-Goo off on a crazed mission to find the root of the evil pestilence destroying his town and his family.

Na makes things scary without resorting to jolt scares or quick edits. The movie unfolds, sometimes slowly, in a way that maintains a high level of tension and creepiness. He mixes in some humor, even during some of the more grisly scenes.

The movie is over 2 ½ hours long, and it makes you work a bit, but it’s all worth it in the end. Kwak is especially good as the father figure who thinks he has it all together, only to find out any sense of security he thinks he’s giving his family can be wiped out in an instant.

The Wailing is genuine nightmare fuel, and another strong entry to the horror genre, which is experiencing one of its periodic renaissances these last few years.