At first sight this looked like a sure fire win. A more thoughtful plot, plenty of violence, beautiful scenery and an interesting cast though the two leads are new to me. What went wrong with it is harder to pin down as it's all fairly typical.

They spend at least a little time setting the stage so you know what's going on. There's the usual woman in a fridge to provide impetus. There's some beautiful scenery, some great cinematography and some angst ridden protagonists. A star turn by Cha Seung Won channelling the Devil King is fun too.
But I found myself too easily distracted from the backstory and fluff making it harder to be pulled in by the set pieces.

The main fall down for me was a total lack of empathy for the main leads - I didn't really like them so I didn't really care what happened to them - it's a hard hurdle to get over. Neither came across as cool or relatable or even consistent. Every time I started to like them they did something to annoy me. Add in some really brain dead decisions especially later in the film and...meh.

Another pet hate of mine is torture porn I get an OOOH! I bet that hurt moment then I get bored and want some plot or action, the best torture scenes are marked by anticipation rather than special effects (cf. the hairdryer scene from Man from Nowhere). You guessed it torture porn rears it's head for too long and with totally unrealistic ability to still function thrown in.

On the plus side there a some excellent shootouts the finale being particularly fun, some comedy gold in places and some great acting. Would I watch it again? Nah! I don't think I'd even skip to the shootouts.