I was exhausted by the time I finished this show! There are so many twists and turns in this story, you need a map. It was an original story, very entertaining, but very emotional. Ji Sung is the male lead, and on a scale of 1 to 10, I'd give him a 20 for this part! He had trauma in his life which cause him to develop multiple personalities. Each personality was so believable and there were so many heartbreaking scenes. I have to score down for two reasons, one was the overabundance of bad guys, and the other was for the female lead, played by Hwang Jung Eum. She tends to stay on the comedy side of the spectrum which was jarring in a lot of the scenes - her screaming and shrieking were very distracting. She was much better in the emotional scenes toward the end. I felt the ending was rushed after all the drama they went through, but this show has one of the best lines ever in ep 1 "Remember - January 7, 2015 at 10:00 on the dot. The time I fell for you." If for no other reason, watch this for Ji Sung's acting.