 SPOILER: After the Girl talks to the old man for the last time, as  she looks off into the sky, a small UFO hovers across and zips off  real quickly. Its been said that the UFO is actually a time machine  that KyunWoo, as an old man, used to revisit his past. The old man  also makes a brief appearance near the beginning of the film when  KyunWoo and the Girl meet for the first time.