“Just because you’re the prime minister doesn’t mean you get to make up your own facts,” rails Katherine Gun (Keira Knightley) as she watches British premier Tony Blair claim that former Iraqi President Saddam Hussein has weapons of mass destruction. This false claim allows the UK and the United States to invade Iraq in 2003, and Katherine, a translator at the United Kingdom’s intelligence organisation GCHQ, tries to do her bit to prevent the invasion. Is she a traitor or the best kind of patriot?

The movie Official Secrets is based on the “untold true story” of Katherine Gun’s whistleblowing, as recounted in the book The Spy Who Tried to Stop a War by Thomas Mitchell and Marcia Mitchell. “In 2003, as politicians in Britain and the US angle to invade Iraq, GCHQ translator Katharine Gun leaks a classified e-mail that urges spying on members of the UN Security Council to force through the resolution to go to war,” the official synopsis says. “Charged with breaking the Official Secrets Act, and facing imprisonment, Katharine and her lawyers set out to defend her actions.”

Directed by Gavin Hood (Tsotsi, X-Men Origins: Wolverine, Eye in the Sky), the movie examines the true meaning of patriotism and public service. I don’t work for the British government, but the British people, Katherine tells her interrogators. “Her story is about so many different kinds of loyalty: loyalty to your personal conscience, your family and relationships, your government, your country, which does not necessarily equate to the government, and to greater humanity in general,” Hood told The Observer in 2018.

Official Secrets is scheduled to be released in the US on August 23 and in the UK on October 18. The cast includes Ralph Fiennes, Matthew Goode, Matt Smith, Indira Varma and Conleth Hill.