Jason Isaacs has joined the cast of the untitled "Green Zone" thriller directed by Paul Greengrass.

The Working Title/Universal project, scripted by Brian Helgeland, stars Matt Damon, Greg Kinnear and Amy Ryan, and is currently shooting in Spain.

According to Variety, the film is a fictionalized drama set in Iraq after the defeat of Saddam Hussein, inspired by Rajiv Chandrasekaran's book "Imperial Life in the Emerald City: Inside Baghdad's Green Zone" about the blunders of U.S. administrators in attempting to reconstruct the country.

Isaacs will play an American military officer.

Rock 'n' Roll High School was released in 2009.