FLU and TRAIN TO BUSAN revolve about the spread of infection.
Both having a child as a cast, making both films..should I say dramatic? Yeah, dramatic, full of emotions actually.
Ma Dong Seok is in both films, playing antagonist on THE FLU and a real hero in TRAIN TO BUSAN. You'll surely get to hate and love this man!
The finale of both films are really similar to each other. (Don't want to spoil.)

LOVE WEAVES THROUGH A MILLENIUM is the chinese version of the QUEEN IN HYUN'S MAN.