The Co-Star Who Worked Alongside Hayden Panettiere in Her Final Film Shares What He Noticed About Her — and What She Confided in Him

The actress arrived to make a dark psychological thriller, but someone working beside her sensed that her pain extended far beyond the script. During the winter shoot, she quietly shared personal truths that he would understand more than most.

Hayden Panettiere died suddenly at 36 on August 16, 2026, only months after her last movie reached audiences. A day later, one of her co-stars described the woman he encountered on that final set, including the heavy feeling he believed she was carrying and why.

The Script Reached Beyond the Screen

"Sleepwalker," filmed in winter 2025 and released in January 2026, placed Hayden inside an emotionally punishing story. She portrayed a woman grieving the death of her daughter after a tragic car crash while the film also explored domestic abuse.

The subject was especially sensitive for an actress whose private life had included trauma, addiction, postpartum depression, and separation from her child. According to the man acting opposite her, Hayden acknowledged that part of the material felt personal.

That co-star was Justin Chatwin, who first crossed paths with Hayden while she was starring as Claire Bennet in "Heroes." They reconnected nearly two decades later for "Sleepwalker," and Justin said their working relationship quickly became warm and trusting.

"We hit it off great and it was an awesome shoot, but it was about domestic abuse and it was subject matter that may have hit close to home, because she did mention it," Justin told People. "She opened up to me about a lot of things."

Their reunion also left Justin comparing Hayden with the young performer he had known years earlier. This time, something about her felt unmistakably changed. "Hayden seemed different when I met her this time than when I met her in the early years," he said.

His Own Past Made the Signs Hard to Miss

Justin's concern came from personal experience. Sober for 15 years, he understood addiction and believed Hollywood could steadily drain performers who had grown up inside the industry.

Early in the making of "Sleepwalker," Hayden told him about her rehab experience and the trauma she had endured. She also spoke openly with him about her addiction.

Justin understood that other colleagues might remember a cheerful, gracious professional on the set. He did not disagree with that image, but he believed there was more happening beneath it.

"I'm sure that everyone else is going to say, 'Oh, she's amazing. She's such a sweet person on set,' because she was," he said. "But we're trained to be actors, so we're acting on set, you know?"

Still, the actress's warmth was genuine, Justin stressed. What made their connection unusual was her willingness to lower the polished exterior that performers learn to maintain around other people.

"And she is sweet. She had a beautiful heart," he said. "But we're trained to be on, and I really liked spending time with her because she took that off, and she was authentic with me about her life and she opened up about her struggles with addiction."

Justin did not repeat the most private details she shared. He questioned whether her pain began in Hollywood, at home, or through a combination of both. "I could tell she was struggling, and I was like, 'I don't think it's this movie,'" he recalled.

Hayden's emotional state stayed with him because he genuinely enjoyed being around her. He counted her among a small number of women he had especially loved working with, yet beneath their happy experience together, he saw something far more painful.

"I also know that she was really lonely," Justin said.

That observation carries added weight beside the actress's past. She shared 11-year-old Kaya Evdokia Klitschko with her former fiancé, boxer Wladimir Klitschko, but transferred full custody to him in 2018 while battling addiction and postpartum depression.

The Secret Battle Behind Her Biggest Years

Hayden had been working since she was 4, long before she could understand the strain that constant performance might create. At 16, when "Heroes" made her internationally recognizable, she said someone on her professional team introduced her to pills before a red-carpet appearance.

During a September 2022 appearance on "Red Table Talk," Hayden recalled being low on energy when the person offered what they called a "happy pill." She did not view it as a drug at the time and accepted the claim that it would help her handle interviews.

"It did give me that little bit of energy and I didn't feel like, high and out of control, but I did feel happy and like I was looking forward to doing interviews, yes," she said.

Her career kept climbing while her dependence on alcohol and opioids developed away from cameras. "My saving grace is that I couldn't be messy while on set and working," she told People in 2022. "But things kept getting out of control [off set]."

She said drugs and alcohol eventually felt almost necessary to function. Looking back at the first pill, Hayden understood that she had been too young and uninformed to recognize the door it could open.

"I was on top of the world and I ruined it," she said. "I'd think I hit rock bottom, but then there's that trap door that opens."

Motherhood brought another battle. After Kaya's birth in 2014, the actress experienced severe postpartum depression and described her world as drained of color. She made clear that she never wanted to hurt her daughter, but she struggled to spend time with her.

After avoiding alcohol throughout pregnancy, she began drinking again and sometimes slipped away to do it privately.

Her relationship with Wladimir, whom she began dating in 2009, deteriorated as her condition worsened. Hayden said neither of them wanted to be around her, and the brief relief provided by opioids or alcohol was followed by an even deeper emotional crash.

"I would have the shakes when I woke up and could only function with sipping alcohol," she said of her lowest point.

In 2018, the same year "Nashville" ended, Hayden sent 3-year-old Kaya to live with Wladimir in Ukraine. She described relinquishing custody as the hardest and most heartbreaking decision of her life, but believed becoming a better mother required her to seek help.

"I was gonna go work on myself, I was gonna get better, and when I got better then things would change and she could come to me and I could have my time with her," she said. "But that didn't happen."

A Medical Warning She Could Not Ignore

The drinking eventually led to Hayden being hospitalized with jaundice. Doctors warned her that her liver was approaching failure and that her body could no longer recover as it had when she was younger.

She entered rehabilitation for eight months, a stay she credited with giving her practical tools to move through addiction. Recovery, however, was never something she presented as complete or effortless.

"It's an everyday choice, and I'm checking in with myself all the time," she said in 2022. "But I'm just so grateful to be part of this world again, and I will never take it for granted again."

Her personal life carried further anguish. The actress endured a troubled, on-and-off relationship with Brian Hickerson, then lost her younger brother, Jansen Panettiere, in 2023 when he died at 28.

Professionally, she was trying to rebuild. "Scream VI" marked her major return to screen acting in 2023, five years after "Nashville" concluded.

She followed it with three more films, including "Sleepwalker," and contributed her voice to the video game "Until Dawn." In May 2026, she released the memoir "This Is Me: A Reckoning," publicly came out as bisexual, and discussed addiction alongside traumatic experiences from her teenage years.

The Conversations Her Director Will Never Share

Justin was not the only person on "Sleepwalker" who has spoken out. Writer and director Brandon Auman said she talked honestly with him about her recent years and how those experiences informed her performance.

Brandon chose to keep the contents of those discussions private. But in his own words to People, he focused on Hayden's openness and the depth he witnessed while working beside her. "She was such a bright, open, numinous spirit," he said. "I keep thinking back to our time on set and how much she taught me."

The director continued:

"I was struck by how complex and deeply introspective she was. She lived a dozen lives in one short beautiful life. I'll miss her forever."

And Justin finished his conversation with the outlet by calling out the industry. He believed Hayden's addiction history and reported apparent overdose could not be separated from a larger pattern involving young Hollywood performers.

"I felt sad this morning, but I feel angry," he said. "Because I want to point a finger at something for this, and it keeps happening."

Justin remembered Hayden as delightful, candid, and wonderful company on the set. In his eyes, Hayden could still laugh, connect, work, and deliver a committed performance, but the loneliness she carried seemed to belong to a struggle no movie set could resolve.