Watching her grandmother’s story told onscreen wasn’t easy for Dakota Johnson.

In her recent Vanity Fair cover story, the “Cha Cha Real Smooth” star opens up about watching the HBO film “The Girl”, about director Alfred Hitchcock’s treatment of her grandmother, actress Tippi Hedren.

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Hedren had starred in Hitchcock’s films “The Birds” and “Marnie”, and the HBO film details the director’s abusive behaviour toward her, including derailing her career.

“We sat at HBO, my family, and watched that movie together,” Johnson said. “It was one of those moments where you’re just like, How could you not have warned us? We’re in a room with some execs. Maybe this warranted a little conversation beforehand?”

Recalling her grandmother’s reaction, Johnson added, “You look over and you see a woman who’s just been reminded of everything she went through, and it was heartbreaking. She was an amazing actress and [Hitchcock] stopped her from having a career.”

“What happened with my grandmother was horrific because Hitchcock was a tyrant,” Johnson said. “He was talented and prolific — and important in terms of art — but power can poison people.”

Photo: Ryan McGinley/Vanity Fair
Photo: Ryan McGinley/Vanity Fair

Hedren was played in “The Girl” by Sienna Miller, who discussed the role in a 2020 interview, calling what the “Birds” star went through a “really, really traumatizing, appalling experience.”

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Johnson also shared that Hitchcock once sent her mother, Melanie Griffith, a Christmas gift as a young girl, which turned out to be a small replica of her mom, Hedren, in a little coffin.

“It’s alarming and dark and really, really sad for that little girl,” Johnson said of her mother. “Really scary.”