This drama is truly a gem. I cannot recall a time when I have experienced so many emotions watching anything. The crime solving was suspenseful, thrilling, and kept you on the edge of your seat. A lesson lied in each of the cold cases solved. Every decision made had a consequence. The acting of the cast was absolutely phenomenal. You will feel what each character felt. You will cry tears of sadness, guilt, anguish, despair, regret, and even relief. You just couldn't help rooting and hurting for characters like Detective Lee Jae Han. I must have cried in every episode because the acting and writing touched every corner of my heart. There were a good number of twists and turns to keep it refreshing and interesting too. And the ending was completely mind-blowing for me, I did not predict that. One of the best endings I have seen in Asian dramas. I don't know how I'll be able to get over this. This is a truly unforgettable experience. I highly recommend everyone to give this drama a try. You will not regret this!!!