Nam Si-heon / Koo Yeon-jun
Ahn Hyo-seop
Nam Si-heon / Koo Yeon-jun

“One past. One chance to save you.”
A grieving woman magically travels through time to 1998, where she meets a man with an uncanny resemblance to her late love.
Official Trailer [ENG SUB] Official
Nam Si-heon / Koo Yeon-jun
Ahn Hyo-seop
Nam Si-heon / Koo Yeon-jun
Kwon Min-ju / Han Jun-hee
Jeon Yeo-been
Kwon Min-ju / Han Jun-hee
Jung In-gyu
Kang Hoon
Jung In-gyu
Bae Mi-yeong
Jang Hye-jin
Bae Mi-yeong
Bae Chi-won
Park Hyuk-kwon
Bae Chi-won
Sung Hye-mi
Yun Sang-jeong
Sung Hye-mi
Lee Su-jin
Han Ji-won
Lee Su-jin
Byeon Da-hyeon
Song Ji-woo
Byeon Da-hyeon
Park Ji-hui
Kim Yi-kyeong
Park Ji-hui
Se-kwon
Baek Seong-cheol
Se-kwon
Bum-sun
Kim Cheol-yun
Bum-sun
Gye-sun
Lee Joo-sil
Gye-sun
For the non-spoiler part: 1. The time travel is straightforward and easy to follow. No advance time travel theories. No time travel gymnastics. Nothing crazy. Pretty much linear. I strongly advise finishing the entire series first because the show itself explained the linearity of the time travel. Again, it's simple and easy to follow. However… this is the **SPOILER** part. They made a mistake on two things: 1. They dated the murder of Kwon Min-Ju on 1998-10-13. 2. When Han Jun Hee arrived in July 1998, her dialogue was she realised she only had 3 months to save Min-Ju. Yet, in Episode 10/11, when Jung In-Kyu was about to jump to his death, he recalled the Christmas he, Nam Si-Heon, and Kwon Min-Ju, spent together. If Kwon Min-Ju did die on 1998-10-13, then how did he have a memory of spending Christmas together? Kwon Min-Ju was murdered on 1999-10-13. Han Jun-Hee controlled the body of Kwon Min-Ju for almost 15 months. She spent 5 months in 1998; and spent 10 months in 1999. Not 3 months in 1998. I'm not sure how they missed this very important detail; or why they filmed a Christmas scene and included it in Jung In Kyu's memories. If Kwon Min-Ju was indeed murdered in 1998-10-13, then the Christmas scene was not possible. If the Christmas scene was correct, then she died on 1999-10-13.
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