Coen Brothers to Write Steven Spielberg's KGB Movie for Tom Hanks (Exclusive)

The pair's involvement only adds momentum to the project, which now is the leading candidate to be Spielberg's next project, with an eye toward a September shoot in Europe.

The untitled Steven Spielberg-Tom Hanks Cold War thriller at DreamWorks just took an intriguing turn.

Joel and Ethan Coen have come onboard to pen a draft of the screenplay that tells the true story of James Donovan, an attorney who was thrust into the center of the Cold War when he negotiated with the KGB for the release of downed U-2 spy plane pilot Gary Powers.

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The project, which was written by Matt Charman, was set up last year, but Hanks' attachment gave it a major boost in April. The Coen brothers' involvement only adds momentum to the thriller, which could be Spielberg's next project, with an eye toward a September shoot in Europe.

Spielberg has a number of potential films vying for his attention including a religious period drama that DreamWorks is developing with The Weinstein Company; Robopocalypse, a sci-fi tentpole set up at Fox; and Montezuma, which tackles the drama between Spanish conquistador Hernan Cortes and the famous Aztec ruler.

The Lincoln director already is attached to helm the adaptation of Roald Dahl's children's book The BFG for DreamWorks, committing to an early 2015 start for the adaptation. But that leaves room to fit in another movie before then.

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The Coen brothers won screenplay Oscars for No Country for Old Men and Fargo. But the pair also are known to take on screenplays that they will not direct as was the case with the Angelina Jolie-helmed Unbroken. Hanks worked with the Coen brothers on the 2004 crime thriller The Ladykillers.

If Spielberg does make this movie, it would mark the fourth feature-film partnership between the director and the actor. The two previously collaborated on Saving Private Ryan, The Terminal and Catch Me If You Can. They also teamed to produce the HBO miniseries Band of Brothers.

Marc Platt is producing the untitled Cold War project.

The Coen brothers are repped by UTA.

Email: Tatiana.Siegel@THR.com

Twitter: @TatianaSiegel27