林伟栋得了癌病。他为了筹集供弟弟伟梁到外国攻读医科的学费，替私枭招应强抢劫了一批钻石。他得手后把真的藏起来，偷龙转凤将假的交给招，招发觉便把他枪杀了。

　　为了找回钻石，招布下诡计，做成伟梁是杀人嫌疑犯，又安排他的日籍女部下和美救了他，将他藏起来及替他治理枪伤。在和美细心治疗下，伟梁痊愈了，他们亦建立了深厚情谊。

　　伟梁好友警探郭少彬被派侦查此案，他和伟梁无意发现伟栋收藏钻石，和美把钻石抢去，招赶到逼伟梁交出，他们交不出，招正想杀他们，和美突然返回和招发生打斗，打斗中和美被招杀死，伟梁亦把招杀死。

　　

　　Lam has cancer and wants to provide his young brother enough money to study medicine before he dies.He helps gangster Chiu to rob diamonds,but hides the real ones,Chiu sends his Japanese girlfriend to seduce Lam’s brother,Wai-leong,to find out the whereabouts of the stolen diamonds.Wai-leong and his detective friend accidentally discover the diamonds but the Japanase girl snatches them and disappears.Chiu appears and demands the return of the diamonds……