Ten years ago, Tae Young-Jin got himself entangled in the Red Ribbon Killer murder case, resulting in not only the death of his parents but also the loss of his memory. When he wakes from a six-month coma, Tae starts his life with a new identity. Now, years later, using the name David Choi, he returns to New York as a genius profiler. David is recruited by Abram Jackman and becomes a trainee with the Federal Paranormal Agency. He balances FPA training with his own secret investigation into the Red Ribbon Killer. While working on the case, David tries to uncover the past and unlock his memories. Eric Khang has secrets of his own. The vampire has been watching over David since the young man was a teenager living in New York. And now that David is back, Eric is trying to help the other man recover his memories. Working together, the truth will be revealed. But, sometimes things are better left in the past.