A CIA agent goes on the run after a defector accuses her of being a Russian spy.

Twenty-four male students out of seventy-five were selected to take on randomly assigned roles of prisoners and guards in a mock prison situated in the basement of the Stanford psychology building.

Evelyn Salt is a CIA agent and highly respected by all, including her boss, Ted Winter. Out of the blue, a Russian spy walks into their offices and offers a vital piece of information: the President of Russia will be assassinated during his forthcoming visit to New York City to attend the funeral of the recently deceased U.S. Vice President. The name of the assassin: Evelyn Salt. Concerned about the safety of her husband, who she cannot contact, she goes on the run. Winter refuses to accept that she is a mole or a double agent but her actions begin to raise doubts. Just who is Evelyn Salt and what is she planning?