I am not a fan of fantasy dramas or body-swapping dramas, but this has to be one of the best I've watched. All characters fit their persona, and even from the interactions with other characters, you can distinguish each. You will lose track of time as you watch the drama. In one day, I was able to finish nine episodes. The comedy is great. There is visible character development. The main male lead played a role in Crash Landing on You, a great actor. From the first episode, you are also immediately being educated about Korean history and culture. As the show progresses, you can see much more (I even memorized the Korean Kings' song thanks to the first episode). I love the outro, it really fits the drama, the ost is so unique and very enjoyable. Overall, a great show. I would rewatch the drama.