“If you fight with monsters for too long, you become a monster.”

Sandra Bullock stars in Our Brand in Crisis as retired political consultant Jane Bodine, who is suddenly thrust back into politics to help an unpopular South American president win a national election.

The film, which is based off of the 2005 documentary of the same name, sees Bullock fight with rival consultant Billy Bob Thornton to show the people of Bolivia President Pedro Gallo, who is being played by Joaquin de Almeida, is a man of the people, after he finds himself down 28 points to a rival candidate.

USA TODAY reports Bullock’s part was originally written for George Clooney

Our Brand in Crisis also stars Anthony Mackie, Scott McNairy, Zoe Kazan and Ann Dowd, and is directed by David Gordon Green.

The Warner Bros. film will debut on October 30.

Watch the trailer: