10/10 is my rating. I really liked both the male (Seo Kang-jun) and female (Gong Seung-yeon) leads in this drama. This 2018 South Korean drama spans 36 episodes (although most places you watch it the episodes are combined with 18 episodes with a "split" in the middle and they wind up being about an hour so equivalent to most that would just run 18 episodes). It explores the very complex issue of when robots become so complex that they are virtually indistinguishable from humans can humans develop feelings and relationships with them. Dr. Oh (Oh Laura) is a mother and a robot scientist well ahead of her time. When her husband dies/commits suicide/is murdered (that is part of the mystery) the grandfather takes her young son who will be heir to the family business and fortune. He puts mother and son (Nam Shim) in a position where neither feel they can subvert the grandfather's wishes without harm coming to the other. Still grieving over the loss of her husband and her separation from her young son, Dr. Oh develops robots to mirror the image of her son as he grows. When tragedy strikes she has the robot stand in for the real Nam Shim to hold his place in the line of succession.

spoiler ? Nam Shim's female body guard (Kang So-bong) and many of Nam Shim's co-workers try to figure out why the son seems to undergo a dramatic change in character (for the better). Slowly the body guard begins to develop feelings for the robot thinking, at first, he is human. When she discovers his secret you wonder if her feelings will change. The male lead plays both the human and the robot so masterfully they really seem like two distinct characters. There is not so much a chemistry between the male and female leads (that would be a bit weird) as there is just this sense of two that perfectly complement each other. There is a villain, of course, who tried to kill Nam Shim once (which is the reason he is in a coma) and threatens to kill and/or remove anyone who gets in his way. I really liked this one because it is like a window to the future and questions what it means to be human. It was not hard to understand So-bong's feelings as many of us develop some emotional attachment to objects in our life such as our car or maybe our electronic vacuum. And those are simple and cannot respond back to us. I liked this drama the entire way through and was sorry when it ended as I so enjoyed my time with these characters. I thought it ended nicely and all of the major plot points were wrapped up. This is up with my all time favorites and I highly recommend it.