Unknown is a 2011 British-German-French psychological thriller film directed by Jaume Collet-Serra, starring Liam Neeson, Diane Kruger, January Jones, Aidan Quinn, Bruno Ganz, and Frank Langella. The film is based on the 2003 French novel published in English as Out of My Head, by Didier Van Cauwelaert. Dr. Martin Harris and his wife Liz arrive in Berlin for a biotechnology summit. However, upon arriving at Hotel Adlon, Martin realizes his briefcase was left at the airport. He takes a taxicab driven by a woman named Gina, but on the way to the airport, the cab crashes off a bridge into the river, knocking Martin unconscious on impact. Gina saves him from drowning, then flees the scene to avoid police because she is an illegal immigrant from Bosnia and Herzegovina. On Thanksgiving day, Martin regains consciousness at the hospital after being in a coma for four days. Martin returns to his hotel and discovers another man with his wife, who claims she does not know him. He attempts to cont...