The series features Octavia Spencer as Poppy, a journalist who examines investigations for her true crime podcast. Union joins Season 3 as a high school principal who works with Poppy to shed light on Black girls who were assaulted and had gone missing in Oakland, California.
Union said when Spencer reached out to her about the role, she was "nervous because of the subject matter" as it led the actress to explore more of her own traumatic experiences.
"At 19, I experienced sexual violence. I was raped at gunpoint at my job," Union said during an interview with CBS Mornings Tuesday. "Throughout the filming of this show, I realized the depths of disassociation."
The 50-year-old actress had been open about her assault in the past, writing about it in her 2017 book, "We're Going To Need More Wine." She said while filming "Truth" she realized she was still disassociating from the traumatic incident.
"Over those five months, it was like my brain was pulling back the curtain on everything," Union said, noting that filming triggered memories of the assault including smells and what "his skin felt like."
"I struggled. I cried and I'm not a weepy person at all. I would go home every night and I would cry, " Union said, sharing that her husband Dwyane Wade would ask her "What's happening?'"
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She continued: "It was like finally feeling the full brunt of my rape and having to use that pain for art for the greater good."
Union said she hopes the show brings attention to a "massive disparity" in media coverage of Black girls who have gone missing in the U.S. According to the National Crime Information Center 2021 Missing Person report nearly 74,000 Black girls under the age of 20 were reported as missing.
"Black and brown girls get adultified. We are demonized and we are blamed for our own abuse, which means you're not going to take it as seriously. Our innocence is never guaranteed," Union said.
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This article originally appeared on USA TODAY: Gabrielle Union cried 'every night' filming 'Truth Be Told' Season 3