A philosophy professor wants to leave her hotel to go to her parents' on Christmas Eve, but is stopped by the police and locked in a room with an officer. She is suspected to have plotted an extremist terror attack.

On Christmas eve, Philosophy lecturer Judith is held up by policeman Thomas because she is suspected of planning a terrorist attack. He has to find out the truth. Judith wants to visit her parents when she is arrested by Thomas in her hotel room. Thomas is to find out if Judith and her former husband Julian are to detonate a bomb that evening and where it is hidden. Judith protests her innocence. Thomas is pressed for time to find out the truth. The more time elapses the harsher his methods of investigation become. He reveals to Judith that he knows a lot about her life due to the preceding observations: relationships, political affiliations, her past. She continues to protest her innocence and plunges Thomas time and again into discussions about the dilemma of freedom and security. Will she confess or will she convince Thomas of her innocence?