I actually watched this drama because of Jo Jin Woong. Not expecting too much about the drama. I didnt know that this drama will be so awesome! This drama deserves an awards! Story: Unique plot, the storyline is amazing. The writer and the director did a great job. Its hard to watch it every week waiting for new episodes. You cant predict what will happen next. They always surpassed my expectations every week. Mixed emotions. 10 out of 10 for the story. Actors: How I loved the cast soooooooo much! They are awesome portraying the characters! Jo Jin Woong can make you fall in love with him!A very charismatic actor. He's amazing! Kim Hye Soo, its my first time watching her and oh gosh she's amazing! She did well on portraying her character from the past and present. Lee Jae Hoon, it is also my first time watching him on a drama. He did great also. I am actually fine on his acting. The other cast are also great! The villains are awesome, the Cold Case Squad Team and also Haeyoung's younger version. 10 out of 10 for the acting. Music: The OST's are awesome. They are all suit to the drama. Its tempting to buy OST Album kkkk~ Rewatch: Of course I'll be watching it again! Signal makes my drama standards even more higher! Hahahaha P.S. For those who are worried about the ending, you'll never dissapoint about it. Believe me :)