In the near future, cloning is now technically advanced, but human cloning is still illegal. Adam Gibson (Schwarzenegger) returns home after working with his friend Hank Morgan (Rapaport), only to find a clone of himself with his family. Before he has chance to find out the truth, he is attacked by a group who want him dead. Adam must escape and find out the truth from the creator of the clones, Michael Drucker (Goldwyn). Adam knows for sure he couldn't have been cloned, but isn't ready for what he's about to hear. 关心未来。谁是我——再看《第六日》。问题的症结并不在于克隆本身。论三次反转。我忘了很多的情节但我深深记得快结束时那个镜头。不再依靠编剧的科幻。让我看后更自卑的电影。克隆与思想。人类想当神。每个死两次 日。 克隆技术在不远的未来有了长足的进步，但复制人仍是法理上不可逾越的禁区，政府通过《第六天法》严格禁止克隆人。 飞行员亚当（Arnold Schwarzenegger 饰）拥有幸福的家庭，他出于本能的厌恶那些违背自然规律的基因技术。亚当平时的工作是和搭档送游客上雪峰，这天他们为宠物克隆公司的老板恰克（Tony Goldwyn 饰）服务，搭档顶替亚当驾驶却发生了意外……回到家中的亚当发现居然有一个克隆人顶替了自己的位置参加他的生日宴，莫名惊恐之下他又被来路不明的杀手追杀，他很快明白自己成为了宠物克隆公司的人类复制试验品，做为母体，他面临被消灭的危险。 在逃亡的过程中亚当与暴力反对克隆人计划的组织合作，成功潜入宠物克隆公司，并控制了克隆人技术的负责人威尔博士……
