Since dropping out from the medical school, Lau Mack has been living a humble but contented life, running a small clinic in a shabby area, treating local inhabitants and poor prostitutes working there. One night, he escorts an injured gun robber to the government hospital, where he unexpectedly meets his old friend from college time, Dr. Jaw, now a reputed surgeon with an aspiration for senior management. To Jaw's bitter surprise, he finds himself outshone by Lau's medical talent and kindness to patients. Jaw is however determined to speed up his career ascent at the expense of Lau. His plots work perfectly, until an accident delivers his life to the mercy of Lau. 香港有个灯笼街----都市文化角度。有谁会不喜欢这样的一个男人。搞笑台词。刘文医生（粤语“刘文”即为谐音“流氓”）。浪子的美好都市。艺术地生活——刘文医生。流氓于世。忍把浮名换取一生逍遥游。男人的坏。流氓医生。 医生刘文（梁朝伟 饰）表面是个玩世不恭的人，但他实际非常细腻、洞悉世情的人。他厌恶不公的医疗制度，决定到红灯区经营诊所。醉心医学的他医术高强，面对贫苦大众好施医德。在他的病人当中有英勇的警员（刘青云 饰）、风月女子等等。他除了医治病人身体上的伤痛，还乐于倾听这群草根的心声，成为了他们的好友。但他却被昔日的好友陷害，刘文面临被吊销医生执照的危机。
