This is my first time reviewing a drama. It's as interesting as any other thriller korean drama. At first I thought to drop it. But I'm sure you won't regret watching it after completion. First two episodes might be boring, but things get interesting after that. It's not a must watch drama. If you are struggling to pick a drama, that too mysterious and fantasy one, you can l pick it undoubtedly. One more thing. This is a kind of new storyline. And an alert. Make sure to watch it when you have a completely free day coz you can't stop it in middle.