A Bittersweet Life opens with a gorgeous black and white image of a willow tree tossing in the breeze. As color slowly starts to bleed into the frame, we hear a voiceover by the main character Sun-woo: "On a clear spring day, a disciple looked at some branches blowing in the wind, and asked, 'Master, is it the branches that are moving, or the wind?' Without even looking to where his pupil was pointing, the teacher smiled and said, 'That which moves is neither the branches nor the wind, it is your heart and mind.'" Sun-woo (Lee Byung-heon) is a man whose heart and mind remain closed to wind, rain, or disruptive emotions. For the past seven years he has served his gangster boss with unflinching exactitude. He manages an upscale bar called La Dolce Vita (which echoes the film's original Korean title), and he despatches people who get in the boss's way with skill and efficiency. The boss (Kim Young-cheol) trusts him so much that he asks Sun-woo to look after his mistress (Shin Min-ah), and to kill her if she is being unfaithful.