Valerie Plame (NAOMI WATTS) and Joseph Wilson (SEAN PENN) are a married couple with two young kids who tolerate dinner parties where their friends and acquaintances express their opinions about the political doings of 2002. While they know Joseph is a former U.S. Ambassador, little do they realize he does secret investigatory work for the CIA. Or that he gets such assignments due to Valerie actually being a covert agent who's recently been promoted to head the agency's Counter-Proliferation division investigating whether Iraq is trying to build weapons of mass destruction.
Along with her boss, Paul (TIM GRIFFIN), and others, Valerie examines the evidence and interviews various people who might have knowledge about such activities. That includes Zahraa (LIRAZ CHARHI) whose brother, Hamed (KHALED NABAWY), is a former Iraqi scientist. As Valerie arranges to get him and his family to safety out of Iraq, Joseph is sent to Niger to investigate whether the Iraqis have purchased 500 tons of uranium as reported. When he learns that never happened, but White House Officials are continuing to spread the story that it did, he writes an op-ed in the New York Times detailing his observation.
This infuriates the likes of Scooter Libby (DAVID ANDREWS) and other White House officials. As a result, and to get revenge on Joseph, Valerie is outed to a reporter and her name and occupation are published in the newspaper. As she tries to do damage control but gets no support from those above her, including Jim Pavitt (BRUCE McGILL), Joseph goes on the warpath, hitting every media outlet he can to let the country and world know what's happened. All of that puts a strain on their marriage, with her confiding in her father, Sam Plame (SAM SHEPARD), about what's occurred. From that point on, they must figure out the right thing to do.