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Dr.Martin Harris (Liam Neeson) awake's to find himself in hospital and is informed by medical staff that he has been in a coma for the past four day's due to being involved in a near fatal car accident.

With little to no knowledge of the event's leading up to the accident and with his own wife not recognising him, Harris must try piece together what occured and why he find's himself being tracked down by assassin's.

So 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?