1930年代,小云、小红(周璇)姐妹被人骗到上海卖给琴师和妓院老鸨夫妇,小云被迫做了暗娼,小红年纪尚小,又天生有一副好嗓子,便随琴师去茶楼终日卖唱。姐妹两人住在贫民窟,在她们对面,住的分别是报贩老王和吹鼓手陈少平(赵丹)。因为闲来无事时陈少平常同小红对窗玩闹,两人渐生感情。 小红卖唱时被流氓古成龙缠上,对方欲强霸她为妾,小红找陈少平商量对策,两人本想借助律师将正义伸张,不想律师双眼只认钱,无奈之下只得逃走,而这一过程中,老王对小云由怜生爱,可是小云却因自卑不敢正视。琴师偶知陈少平与小红下落,放风给古成龙,古成龙赶到小红住处时,屋里只有她和小云,两人生命危在旦夕。
在世界末日后的荒原上,两姐妹离开堡垒去救受伤的母亲。她们只带着一辆肌肉车和有限的弹药,与无情的袭击者赛跑,从遥远的前哨基地夺取救命物资。
Based on actual events of American serial killer Edmund Kemper, who murdered his grandparents at age 15 and, after being paroled for that crime, killed eight women in 1972 and 1973 including his own mother.