40年代的广州。黑社会头目捞家七的保镖李彪随身拎着一个藤箱匆匆从香港返回。与此同时青年洪伟华大学毕业赴广州谋生，与李彪同时抵达羊城，他手中也拎着一个藤箱。因为人地生疏，洪伟华决定先找到同学梁展鹏。当他正向卖烟老人询问时，忽听女人呼救，他放下藤箱，去追抢钱包的小偷。李彪乘坐的人力车停在烟摊前。他放下藤箱买烟。被洪伟华追赶的小偷奔逃时撞翻烟摊，李彪恼火地提起藤箱走了。洪伟华帮助那位小姐追回钱包，才想起箱子还在烟摊前。他终于找到梁展鹏，应邀住在他家。傍晚，他打开箱子，惊奇地发现里面装满了外国烟而不是他的衣物。趁他走开时好奇地打开一条烟，里面掉出几个装着毒品的小塑料袋。而发现藤箱里的烟不翼而飞的捞家七则以为李彪竟敢在他身上做手脚，命手下白金龙痛打李彪，李彪吓得面无人色，极力否认时猛然想起他在烟摊被人撞倒后可能拿错了箱子。他和白金龙拿着洪伟华箱中的信件寻到了梁展鹏家，但只找回了空箱，里面的毒品已被梁展鹏取走，结果，不明底细的梁父惨遭杀害。闻讯懊悔不已的梁展鹏，决心以毒品为诱饵替父报仇，却中了白金龙的圈套，被打成重伤，跳下珠江。早已离开梁家的洪伟华对一切一无所知，他在路边偶遇上次被抢的小姐——富商孔寿年的干金孔丽珊。两人闲谈时，白金龙追至逼他交出毒品，两人仓皇逃跑。捞家七向孔家强索钱财，孔父严斥孔丽珊。洪伟华从梁展鹏之妹口中得知一切，后悔因自己牵连梁家家破人亡。在孔丽珊的指点下，他从捞宅后门潜入找捞家七算帐，因势单力薄，被打得遍体鳞伤，危急时被孔丽珊救出。白金龙背叛捞家七，绑架了孔丽珊向孔家勒索。捞家七带人与白金龙厮杀，死于白金龙暗器之下。洪伟华救出孔丽珊后与白金龙相遇。梁展鹏出现，为报杀父之仇，他拉响手榴弹，与白金龙同归于尽。

A 20-year old young man who has been brought up by a foster mother in the countryside has fallen in love with another foster child in the same "family" and the two have decided to get married. Just after this decision, the young man's real mother contacts him and asks him to come and stay with her and his father (she is a high-ranking Party official). She is against his marriage but her husband is not. In the end, the young man decides to marry at the home of his real parents, and when his foster mother shows up, his real mother treats her like dirt - it turns out that the foster mother was a concubine for awhile. Before things deteriorate any further, the husband has some news for his wife that helps her to see the foster mother in a different light.