SPOILER ALERT!!!
You can listen to Wong Kar-wai's movies like a radio play: Invisible vibrations between the characters, the rooms where they stay in, the rhythm that presses them ahead, attraction and dislike - the whole spectrum of the atmosphere is played back by the sound track. The dialogue is mostly completely unimportant.
The narration is similar to a childish amorous look at a beautiful woman and a sad man whose sorrows are noticeable, but helpless. "In The Mood For Love" is told from a child perspective, but the child never appears as a narrator. The aesthetic of the film is developed by an extreme light and color dramaturgy, harsh cuts, an unattached, almost documentary camera and a complex, unobtrusive sound.
The genius use of Nat King Cole's "Perhaps, Perhaps, Perhaps", whose mysterious power grows the more often it is repeated and the melancholic waltz helps in the graceful choreography of the two protagonists. Maggie Cheung in her beautiful dresses is brilliant, the perfect vis-à-vis to the handsome, stylish Tony Leung. The audience assumes a romance between them, but Wong just sees sad resignation. The two potential lovers are revolving around each other like satellites, knowing that they never will share the same orbit. You wish that they will find each other. They won't and the emotional power of their non-love-sex-relationship makes the movie immensely fascinating.
It is about broken luck and unspoken love. In all of Wong's films these are the leitmotives. Love, whether it comes too early or it comes too late to take the one and not the other person. The yearning of the characters that is never satisfied, their loneliness, the mourning, and the luck that they experience when it is too late.