This drama was a piece of art. The actors did an amazing job especially Jang Se Yeon (Han Ga In). Each character has its own story and secrets and this is why i finished watching this drama in two days because each episode makes u more curious and more attracted to it. And the romance wasn't forced into the drama like many other mystery dramas it was actually just in place which made me love this drama even more . Totally worth watching.
PS: i gave the rewatch value 1 because once secrets are revealed and the mystery is solved you have no reason for watching the drama again.