Kanye West & Maggie Gyllenhaal: 'River of Fundament' Premiere!

Kanye West keeps it cool and casual as he attends the world premiere of River Of Fundament held at the BAM Harvey Theater on Wednesday (February 12) in New York City.

The 36-year-old entertainer was joined by Maggie Gyllenhaal, her husband Peter Sarsgaard, director Matthew Barney, and his longtime muse and collaborator, Aimee Mullins, who is the star of the flick.

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Shot over a period of six years, River of Fundament is an operatic film in three acts inspired by Norman Mailer‘s novel “Ancient Evenings.”

FYI: Maggie is wearing a Prada dress and bag, Manolo Blahnik shoes, and Fred Leighton jewels.

10+ pictures inside of Kanye West and others at the River of Fundament premiere…