马丁·哈里斯博士(连姆·尼森 Liam Neeson 饰)到柏林参加学术交流,却不幸遭遇了一场车祸,昏迷中醒来的他发现自己整个人生都被偷走了,妻子伊丽莎白(詹纽瑞·琼斯 January Jones 饰)不再认识他,而另一个人(艾丹·奎因 Aidan Quinn 饰) 取代了他的身份,成了哈里斯博士,光明正大出现在学术会议里,似乎所有人都认为那才是真正的哈里斯博士,令马丁十分迷惑。没有人相信马丁的说辞,柏林当地警署对他的申诉置若罔闻,又似乎有人开始追杀他。异国他乡,举目无亲,身陷险境,是人们的记忆被偷走了?还是自己脑袋出了问题?又或者背后有惊天阴谋?马丁走投无路之时,一个神秘女人吉娜(戴安·克鲁格 Diane Kruger 饰)出现了,似乎能帮他找到事情的真相……A biochemist and his dishy wife arrive in Berlin for a conference at which a scientist and his controversial Arab funder will announce breakthrough research. While his wife checks into the hotel, he grabs a cab to return to the airport for his briefcase, left at the curb. En route, an auto accident puts him in a coma, from which he awakes four days later without identification and with gaps in his memory. He goes to the hotel: his wife refuses to recognize him and another man has claimed his identity. With help from a nurse, the cab driver, a retired Stasi agent, and an academic friend, he tries to unravel what's going on. Is the answer in the briefcase?