香港高级警司罗聪天触犯贪污条例，被迫逃往美国，其子罗宾在港夺得黑帮名册，赶往美国交给聪天，希望能洗脱父贪污的罪名，黑帮杀手亚健、小文追踪至美国。摧花狂魔魔鬼鱼四处作案，残害少妇。罗宾之弟米高和街头女霸王大姐大之妹一同遇害，罗宾与大姐大发誓要掀到凶犯。亚健、小文勾结美国黑帮暗杀了聪天，但名册却失踪，追查魔鬼鱼的罗宾又被亚健一伙追杀，在其腹背后敌之际，邂逅了聪天的义女珊珊，得知名册由她保存，罗宾与大姐大在警方的配合下消灭了魔鬼鱼，亚健一伙也被绳之以法。最后罗宾携带名册，只身上路……

In Cecil B. DeMille’s 1920 comedy Why Change Your Wife? Gloria Swanson (DeMille’s regular leading lady of this period) as Beth, a respectable and rather prim wife who discovers that husbands don’t necessarily want their wives to be respectable and moral. It’s not that he doesn’t love her; he just wants a little romance in his marriage, and when another woman comes along who offers him the excitement he craves, he inevitably strays. And divorce inevitable follows. Beth then has a sudden revelation – maybe it’s not only true that men like shameless hussies, but maybe it’s also true that shameless hussies have quite a lot of fun. So she decides to transform herself into a sexpot.