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Troian Bellisario's first big move post-Pretty Little Liars isn't for the faint at heart.

In Feed, the actress plays Olivia Grey—an 18-year-old twin "born into a world of privilege and high expectations," according to Entertainment Weekly, who must learn how to live without her brother Matthew Grey (Tom Felton) after tragedy strikes right before their senior year of high school.

The feature film marks the first that Bellisario has ever written. She also is a producer on the film, which is based on her own experience with anorexia. In the trailer, Bellisario can be seen running down a street as well as playing with her food instead of eating it. At one point, her bony back is visible in a locker room, as a friend walks in and startles her, saying, "You look sick."

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"I'm so proud to share this story with you," the PLL star said on Instagram Wednesday. "So grateful to my best friend and artistic partner in crime @docdanger for directing it, to @t22felton for playing my other half, Matt and everyone who worked so hard to make this dream a reality. A huge thank you as well to the incredibly talented @witchoria for making us a beautiful piece of art for a poster!"