07/17/2009 at 06:35 PM EDT
As the star of her new thriller Homecoming
, Mischa Barton
would have basked in the limelight of her premiere in New York City on Thursday night.
Instead, she remained hospitalized
in Los Angeles after police were called to her home earlier in the week for assistance. Her rep told PEOPLE that on the "recommendation of her doctor" she was resting in a hospital.
But Barton was missed by the director and producers of her new film, who wished her a speedy recovery.
"I'm very concerned about [Mischa]," says Austin Stark, a producer on the film. "First and foremost, we hope she gets better. I don't know exactly what happened ... I wish she wasn't going through the turmoil that she is right now."
Barton's performance in Homecoming
is good in its own right, said executive producer Benji Kohn. "We wish her the best in her personal life. And we hope the movie just stands on it's own," he said.
Cohn noted that Barton's mother, Nuala, was an executive producer on the film as well and spent most of her time on set.
"She made sure that Mischa was happy and that things were working out for her," Kohn says of Barton's mother.
The news of the actress' hospitalization quickly circulated among the film's production. "There was the shock, and then 'God, I hope she's okay,'" says director Morgan J. Freeman, who sent along his thoughts and prayers to Barton.
Barton's next project is starring in The CW's new drama The Beautiful Life
. A rep for the show tells PEOPLE the start has been pushed to July 31 due to set issues.
With reporting by LISA INGRASSIA