Tony Leung Chiu Wai acts as Dr Mack, a wisecracking medical genius, who believe it or not, has no license to practice in HK, but does a good job treating his patients, and still manages to look cool nonetheless. When it comes to the most difficult operations, he is able to carry it out. Sadly, his life is quite a mess. He and his classmate, Roger Law (played by Alex To) fall for the same girl, but he gives her up because he feels he cannot be a good husband to her. She returns to find him to seek treatment when she is dying of bone cancer. He treats her, but she still dies.