Joining Steve Carell and Channing Tatum, Miller is set to play the wife of Ruffalo's character, an Olympic gold medalist who was killed by his paranoid friend in 1966.
Bennett Miller's tragic crime movie "Foxcatcher" has added Sienna Miller to its starry cast ensemble. According to Deadline, the fiance of Tom Sturridge will star as the wife of Mark Ruffalo's character, a wrestler who is killed by his own friend.
The movie is based on true story of John du Pont, a paranoid schizophrenic who built a wrestling training facility on his 800-acre Pennsylvania estate. There, he subsequently shot and killed Olympic gold medal-winning wrestler David Schultz in 1966.
Heir to his family's chemical fortune, du Pont locked himself in his mansion for two days after murdering his friend, and spent the time on the phone with negotiators. The authorities were finally able to lure the man out of his house when they shut off his power and heat.
Tackling the part of du Pont will be Steve Carell. The fillm is also supported by Channing Tatum who is set to portray Schultz's brother Mark. Marking Miller's follow-up film after his Oscar-nominated "Moneyball", "Foxcatcher" is scheduled to kick off the production this October.
The high-profile project is written by Oscar-winning writers Aaron Sorkin ("The Social Network") and Steven Zaillian ("Schindler's List"). Serving as the producers are such names as Michael De Luca, Rachael Horovitz and Scott Rudin.