4. Oldboy (2003)
Genre: Action, Drama, Mystery, Thriller
IMDB: 8.4/10
Directed by Chan-wook Park, this surely is a bizarre yet brilliant story. This film has one of the most intelligent screenplays. Directly quoting from IMDB, “After being kidnapped and imprisoned for fifteen years, Oh Dae-Su is released, only to find that he must find his captor in five days.” So I will not spoil much by telling the plot in details. Go watch this movie and enjoy.