WATCH: Margaret Qualley Is a Woman Pregnant by a Dead Man in Strange But True Trailer

Margaret Qualley has found her next film.

In a PEOPLE exclusive look at the trailer for Strange But True, the 24-year-old actress and daughter to Andie MacDowell stars as Melissa, a pregnant young woman who claims the father of her child is her high school sweetheart, Ronnie.

The only problem is Ronnie died five years before.

High off her breakthrough role in Quentin Tarantino’s Once Upon a Time… in Hollywood, Qualley as Melissa attempts to convince Ronnie’s family, including his older brother Philip (Nick Robinson) that she’s telling the truth.

“It must seem strange, me showing up here after all these years. I’ve only ever been with Ronnie, the night that he died five years ago,” Melissa says.

She adds, “Now some strange miracle has happened. This baby inside me belongs to Ronnie.”

“It is completely impossible,” Ronnie’s mother, played by Amy Ryan, says.

“I’m not crazy,” Melissa says. “It’s just the only answer that there is.”

Skeptical, Philip asks, “Is it?”

Filled with twists and turns, Strange But True is based on the book by John Searles, which was named a national bestseller. Searles has also written other novels including Boy Still Missing and Help for the Haunted, which won the American Library Association Alex Award and was named an Amazon Top 10 Mystery and Suspense Novel of 2013.

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Greg Kinnear, Brian Cox, Blythe Danner and Aladdin’s Mena Massoud also star in the film.

This is Qualley’s latest film after starring as Pussycat, a member of the Manson Family. The young actress shared most of her screen time with Brad Pitt, who she did a chemistry test after auditioning for the role.

“Quentin said, ‘This is going to be the most fun you’ve ever had making a movie,’” Qualley told Entertainment Weekly. “And he was right.”

Strange But True is in theaters and on demand Sept. 6.