This is truly one under-rated and under-advertised drama. So far, of all the time travel dramas that I have watched, this has to be the one with the most original and ingenious plot. It started off slowly but nicely in Tibet, which sort of set the perfect scene for a mystic journey of time travel. From then on, you will be kept on the edge of your seat as each episode produce one after another unexpected events. I was never able to second guess what exactly will happen next. On many occasions, I was thinking that's it, the story should be completed and it will be happy ending thereafter, but the next twist again proves me completely wrong. . The ending is very meaningful but needs a bit of thought process to appreciate it. Surprisingly, there is not a single loose end to the plot, everything just ties in together perfectly and logically despite the time travel element (which in itself is the most consistent and logical means compared to the other time travel dramas) The highlight of the drama was the charisma of Lee Jin Wook or rather his portrayal of Park Sun Woo. His character's dry humor even when facing with adversity is really spot on and Jin Wook really makes Sun Woo comes alive. The only bad point of this show in my opinion is the lack of quality OST. There is only one (the main one) which left some impression, but the rest or lack-of are forgettable. Don't think this show has much rewatch value after you watched it once because you would have knew all the twists that are going to happen. Also, other than superb acting of Jin Wook, there is really no "star names" in this drama which would prompt you to do a re-watch.