As is the right objection that the plot is lost in the middle,true. Around 15th episode it starts centring around the student of Dr Kang. He has kidnapped her & is at present treating Hyun Bin. The time is right to reveal that he carries a grudge for being left with the kidnapper. In their childhood, both are kidnapped. But Hyun Bin manages to escape & his friend doesn’t.
Too many details make it look like a thriller with Dr Yoon in the center. Without Hyun Bin on screen makes more weird. He is put in the correctional facility & the story again starts for Hyun Bin , his other identity Robin & Han ji min. The series could have been finished in 16 episodes which drags to 20.
The 20th episode is very swiftly ended. Instead some time should have been given to Han ji min to start liking the character. She is made to adjust so fast, when there was so much time it could have made sense to take it slow. The face is the same but the person displays diverse features. Help of Dr Kang would be appreciated.
Blending of the two identities for the spouse is also traumatic. She should have been counselled. At least some mention was needed. The beginning was superb. The developing plot needed more care. As expected it ends well but could have been better. It needed better closure.
With Hyun Bin & Han ji min to look forward to who is complaining! But again I thought he does look better with Son ye jin & now know fans want them to become a couple.