Robin is disconcerted by Gu Seo Jin (Hyun Bin)'s altruistic attitude which to coexist with him for Jang Ha Na (Han Ji Min).
Robin (Hyun Bin) forgetting a lot of things visits Kang Hee Ae (Shin Eun Jung) to ask her to get extinction treatment in a week.
Ha Na grieves as she realizes Robin is leaving in a week.
Robin leave a message which sincerely asks Gu Seo Jin to take care of Ha Na after he disappears.
Robin says sobbing, "I'm Robin if I lose a leg or arm, however, I'm not me if I lose past memory."
He wants to leave with the happy memory with Ha Na and he is terribly distressed by the lost memories with her.
Gang Ha Na decides to say goodbye and asks friends to prepare their wedding to make him the best memory before his leaving. She proposes Robin.
Hyde, Jekyll, Me Episode 19 was sooooooo sad despite of the lowest audience rating.