故事围绕着一幢破旧的旧式大院展开，着力描画了租住在此的七十二家房客的众生相。众房客在包租婆八姑的欺压下，终日不得安生。八姑风骚刁泼，待人刻薄。而她的养女阿香却乐于助人。终于，八姑的苛刻规定“房客每天只能用两桶水”成为了导火索，做洗熨的上海婆带头抗议，得到房客们的合力支持。加上发仔、阿福等人的附和，一段段斗智斗勇的小故事连番上演。

Set during a period of depression, the film chronicles the daily lives of a single urban building split up into several separate units, and the actual people that dwell within.