Watch "Unknown" online for free.

In "Unknown", Liam Neesson plays a happily married biochemist who is about to get new funding for his important scientific project. En route to the airport, he becomes the victim of an awful car crash, which leaves him in a coma for four days. When he wakes up, he finds out that someone else has taken on his identity, and no one, not even his wife, seems to recognize him. With the help of a few old and new friends, he sets out to prove that an imposter has taken over his life.