Short: If there was ever a role that suited Hwang Jung Eum, this is it. Many good fun moments, general warm message of helping people through their "grudges". Some good music, and an original story with interesting characters played by a superb cast make this one an easy win.

Detailed:
So much fun :)

It's 12 episodes, which allows it to remain punchy and stay on point. Many amusing moments come out of Wol joo's character being something of a brat, constantly acting up and bossing people around, particularly her faithful sidekick.

It just looks like the cast, directors, writer had a blast - there's a lot of energy in it and numerous times that some interesting scenes were in there that perhaps didn't even need to be (like one scene where she turns to face the camera, breaks the fourth wall and sends out some facts to the viewers, or another where they subtly introduce 'the new guy in heaven' - Steve Jobs of Apple, who's sitting there taking one bite out of an apple in just *that* place) - but the presence of them just made it all the more fun.

It has a good message, everything you do reflects on you later, whether it's big or small, good or bad, it will come back to you later.

If there was ever a role that Hwang Jung Eum's very extrovert acting style suited this one is absolutely it, even if you haven't appreciated her as much in other roles give this one a shot, it's spot on :)

I particularly enjoyed Jung Da Eun's character, Yeo Rin, the security guard. She takes no prisoners, she's tough, but she's still a person and shows warmth as well.

Highly watchable, definitely recommended :)

Why only 9.5 and not 10? It's not "goblin" good or "crash landing" good, but I can't bear to give it even a 9, so i've gone for 9.5 :) There's no science there at all! :)