The place where the two stayed is the base of the Independence Army in Shizuoka Prefecture, Japan. However, the actual filming location is an island located in Sinan, Jeollanam-do.
Although this scene is in the mid-to-late part of the movie’s flow, the actual filming took place in the early part.
Originally there were no lines in the scene where Deokhye treated Kim Jang-han, who was injured, but Son Ye-jin added the line “Hang in there” to inject tension.
The scene where Deokhye warmed herself and rubbed her face with her hands was created by adding Son Ye-jin‘s idea to the existing script.
Source: Daum
