Sienna Miller is in talks to star alongside Bradley Cooper in American Sniper, which is now being directed by Clint Eastwood after Steven Spielberg bowed out in August.

The project is based on the memoir of the same name written by Navy SEAL sniper Chris Kyle, who has the most confirmed kills of any sniper in U.S. military history. Sienna Miller is playing the soldier's wife, who is raising his kids while he is off fighting overseas. Clint Eastwood reportedly spent the past week deciding between Sienna Miller and Jaimie Alexander (Thor: The Dark World) for the role. Kate Mara was a contender for the role, but she was forced to drop out after signing on to play Sue Storm in The Fantastic Four.

Jason Dean Hall (Paranoia, Spread) wrote the adapted screenplay, with Bradley Cooper, Andrew Lazar and Peter Morgan producing. Shooting is scheduled to begin next month.

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Sienna Miller most recently starred in A Case of You, and she will next be seen in Foxcatcher.