Ben Platt and Lola Kirke Take on Sibling Rivalry and Schizophrenia in 'Broken Diamonds' Trailer (Exclusive)

After their dad dies, a younger brother must care for his schizophrenic sister.

Family trauma. Mental health. Complicated sibling dynamics. Ben Platt will tackle it all via sing in Dear Evan Hansen, but it's also at the heart of his upcoming drama, Broken Diamonds. And ET has the exclusive trailer debut.

In Broken Diamonds, Platt plays Scott, an aspiring writer moving to Paris to make his dreams come true. But when his father dies, his plans are derailed as he must return to the family he left behind, including his stepmom (Yvette Nicole Brown) and older sister, Cindy (Lola Kirke), who is living with schizophrenia.

After Cindy is kicked out of her care facility, Scott becomes her unwitting caretaker as the two must come to terms with their shared past and figure out their futures. Screenwriter Steve Waverly based the film on his own experience with his sister. Watch the trailer above.

"Ben is one of those wonderful actors that can make you cry one moment and laugh the next," director Peter Sattler tells ET. "There's a sincerity and emotionality to his work that was really essential to telling this story in a way that was honest about the disease, but also filled with the laughter and love that can thrive between a brother and sister, no matter how dire the circumstances they find themselves in."

As for Kirke, the filmmaker knew she was right for the role the first time she read opposite Platt. "I knew immediately that she was the only person who could play the role properly," Sattler says. "She always treated her character as a person first, not just as her disease, which is the entire message of the movie. Her self-assured vibrancy coupled with the ability to convey vulnerability and insecurity made her the perfect actress to pull off a truly challenging role."

FilmRise

Broken Diamonds is in theaters on July 23 and available on demand Aug. 23.

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