Liu Zhi Kang (played by Tony Leung) is a violinist, Cai Jia Yi (played by GiGi Leung) is a writer who makes a living from translation. The two live in the same apartment building, but due to their different habits - one walks to the left, and one walks to the right - they have never met. These two lonely urban men and women, although in a very realistic environment, still adhere to their ideals and are full of hope for love.