Justin Chatwin is "pissed off" over Hollywood culture as he grieves the death of his "Sleepwalker" co-star Hayden Panettiere.
In an exclusive interview with Fox News Digital, Chatwin — who recently worked alongside Panettiere on what became her final film — said his grief has turned to anger over what he sees as a lack of support for people struggling with trauma and addiction in the entertainment industry.
"I'm a man, so I process things by getting pissed off," Chatwin said. "And so I'm kind of angry that this is the culture that — and this is the industry — that people aren't taken care of."
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"They get the work, they sell the product," he continued, "and there's just a lot of people in our industry that are dying from … inability to feel pain or heal trauma."
Chatwin added that "there's not enough support or awareness around these issues," before saying, "Yeah, I'm grieving."
Panettiere died Sunday, Aug. 16, at the age of 36.
The "Heroes" and "Nashville" star was found in cardiac arrest at her home in Greenville, South Carolina, according to the Greenville County Coroner's Office. Emergency personnel attempted life-saving measures before Panettiere was pronounced dead. An autopsy found no signs of trauma that contributed to her death.
Her official cause and manner of death have not yet been determined, and the investigation remains ongoing.
Chatwin said the struggles he witnessed extend far beyond Hollywood, describing trauma and addiction as an issue affecting people across the country.
"It's not just her," Chatwin said. "We've lost a lot of people, and not just Hollywood, in all of America. It's an epidemic that needs to be looked at."
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Chatwin said his final time with Panettiere came after the two finished working together on "Sleepwalker," when they went out to dinner following the film's wrap.
"We went out to dinner after we wrapped the movie and, yeah, she was one of the top five, top 10 favorite people that I've ever worked with," he recalled. "She was super sweet."
However, Chatwin said he could also sense that Panettiere was carrying significant pain.
"I could sense a lot of pain that she had dealt with, from her family to her daughter," he said. "I could sense the heaviness and the weight that the toll of 20 years in Hollywood and … trauma and the fight to figure out the trauma and addiction can have on you."
Panettiere had previously spoken publicly about her struggles with addiction and other personal challenges. She detailed many of those experiences in her 2026 memoir, "This Is Me: A Reckoning."
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Chatwin first met Panettiere years earlier when she was in her 20s and starring on "Heroes." The two later reunited to work together on "Sleepwalker," a psychological thriller released in January. Panettiere starred as Sarah Pangborn, a grieving mother, and also served as an executive producer on the film.
"She's just got one of the biggest hearts of anyone that I've worked with," Chatwin said. "And she's super sweet."
But Chatwin said he noticed a difference in his co-star when they reunited.
"Life had taken a toll on her, and she had a lot of unfortunate incidents," he said.
The actor also opened up about the loneliness that can exist behind the glamour of Hollywood, describing the stark transition performers can experience when they leave a movie set.
"Sometimes the pain is unbearable, and at the end of the day, you go home from a warm, fun movie set where everyone's telling you you're great, and you're alone in your house and you still got to order your coffee and eat your dinner," Chatwin said. "It's a really lonely career."
On set, however, Chatwin remembered Panettiere as "super fun" and said he treasured their deeper conversations.
"I really love having deep conversations with her," he said.
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Reflecting on Panettiere's experience while making "Sleepwalker," Chatwin also offered a warning to fellow performers about taking on roles that could force them to revisit unresolved experiences.
"I think that actors need to consider what roles they play, especially if it's opening up a vulnerable trauma that isn't healed," he said.
Panettiere rose to fame as a child actor before becoming widely known for playing cheerleader Claire Bennet on NBC's "Heroes." She later starred as country singer Juliette Barnes on "Nashville," earning two Golden Globe nominations, and appeared as Kirby Reed in the "Scream" franchise.
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Her death came a little more than three years after her younger brother, Jansen Panettiere, died in 2023 at age 28 from an enlarged heart coupled with aortic valve complications. Panettiere had spoken openly about the profound grief she experienced following his death.
Despite the pain Chatwin said he witnessed, his description of how he hopes Panettiere will be remembered was simple.
"She was a unicorn."
And when asked what Panettiere had told him about returning to acting and what she wanted to do next, Chatwin said her focus wasn't on another role or career milestone.
"I think the only focus was to be happy," he said.
