This drama was so disappointing I'm writing my first review (spoilers ahead).

First of all, it didn't hook me in like most other dramas do, I couldn't watch more than one episode at a time (which is saying something). The first half was decent, but then I got really impatient and would watch half an episode and finish the next day because I got bored (and slightly annoyed at the lead's breathing, feels like he breathes more than he talks - yes, it can be effective, but it was over used).

Cast is fine, acting on the whole is pretty good, music is fantastic (have yet to watch a drama with bad music). The story has an interesting premise, but it lacks/fails in the delivery.

(Spoilers!)
I have issues with the premise that people who commit suicide never make it to heaven (which could just be the 'religion' of the show but that stems from very real stigma) and dissipate. And if that means they never get reborn, how is Kang Pil Sung meeting Hong Seo Jung at the end? (Cheesy.) I thought the souls Hwang Dae Du absorbed wouldn't go to heaven either? Did that change?

Hwang Dae Du apparently has OCD because it's convenient to the story line (except when it's not). If he truly had OCD, you would see his "compulsions [as] repetitive behaviors that [he] feel[s] driven to perform." But you don't. He's kind of 'obsessed' with Kang Pil Sung, and the answer as to why in the last episode is pretty unsatisfying/lame. His whole 'theory' he's out to prove that demons are made, not born, isn't showing at all. He taunts Kang Pil Sung "look at what you've become" and I just "???" I don't see it, until the last episode (briefly), which is too little too late.

There's no telling how or why Hwang Dae Du attains the powers that he does. Yes he swallows a few souls at the beginning (yes the shaman has powers), but after that? On top of getting a few psychic glimpses he can now move & break things? Immobilize & control people? Huh?? There's no explanation for any of his powers, they just show up, 'cause I guess that's cool?

Not to mention, if the whole world is going to hell (because the door is open), how the hell is that not sensed from the island? I can accept Hong Seo Jung doesn't feel Hwang Dae Du because of salt or whatever, but HELL itself? Engulfing the world? A few episodes ago it was made clear the effects were worldwide, so why would this tiny island be exempt??

Towards the end... well, I was surprised (at first) when people got killed, but when new characters were introduced I had an idea of what would happen, and then it did, no surprise. Was there a point to all the deaths? Meh. Later, the girl's rushed to the hospital, "any later and she could've died" from WHAT? Being knocked out? Poisoned? We'll never know! And to top it off, Kang Pil Sung is the suspect of SEVEN murders?? HOW? They literally have video of the other dude TWICE? Details, I guess, but as a writer, I can't let those slide. I don't mind dark/bittersweet/unhappy endings but they have to be done well, and it wasn't. :|