Oldboy is a hybrid genre film that incorporates elements of action, romance, comedy, horror, thriller, detective, noir and surrealism. While drawing on multiple genres, it subverts expectations typical of mainstream films. The film breaks conventions of realistic filmmaking through various experimental techniques, including long takes, minimal CGI, camera movement, color use, split screens and close-ups, which call attention to themselves and remind viewers it is constructed. These techniques reinforce themes of complex characters struggling with identity, loss, loneliness and longing.