This drama is NOT to be taken seriously. SIG is his usually wonderful self, this time bouncing around as a shaman, who is secretly trying to avenge his friend's murder. He used to be a profiler & uses that in his fortune-telling. The team at Cafe Minamdong is just fun, although those who hate slapstick, exaggerated comedy will not like them.
The police team are also fun, although the two junior detectives were a bit over the top even for me. I liked the female lead (really, people! WTF is wrong with her? She's a cop, going after criminals!), and the older mentor just is one of those seasoned Korean actors that brings verisimilitude to every role he takes.
The mystery has an interesting twist - I wondered after about the 8th episode, but it didn't fully reveal itself until nearly the end, and did so in a very good way. I've watched a lot of dramas with this kind of thing before that have not done this as seamlessly or logically, frankly - playing with the audience or using shock value (or both, like Mouse ). This one did it well.
All in all this was just a fun, refreshing drama for me to watch - nothing heavy, satisfying action, very few true plot holes or logic fails (other than some over the top kinds of comedic situations), and just, SIG being very funny & appealing throughout.
I find all the negative reviews ridiculous, frankly.