Watch Shelley Duvall open up about her final role on The Forest Hills set at 75

Shelley Duvall had not appeared on screen for over two decades before she agreed to participate in what ultimately became her last project—an independent horror movie titled The Forest Hills.

The celebrated actress, who passed away at 75 on Thursday, originally agreed to make a brief appearance in the film. The plot revolves around Rico (Chiko Mendez), who experiences disturbing visions following a head injury while camping in the Catskill woods. 

Duvall plays Rico's abusive mother. According to an exclusive behind-the-scenes video, the film's writer and director, Scott Goldberg, reveals that Duvall's role grew larger after her arrival on set.

"Her character was first a cameo role, a Friday the 13th Pamela Voorhees type of flashback," the director explains. "After that scene, she expressed interest in working with someone else on camera. Then being able to finally work with Shelley and be there in person, and actually film with her — she's kind, sweet, gentle, and such an amazing actress."

In the video, Duvall comments, "Working with Scott Goldberg was really exciting because we used a lot of new technologies [and] cameras, and I was amazed at how easy it became to become a filmmaker." 

She continues, "This kind of filmmaking is the future: smaller, more intimate crew that at any time can be increased per the script… and the lighting and all that takes so much less time."

Most recognized for her role alongside Jack Nicholson in The Shining, Duvall retired from acting in 2002 following her appearance in the comedy Manna from Heaven. 

In 2016, she made a comeback with a contentious interview on Dr. Phil's talk show, where she disclosed her struggles with mental illness. The interview sparked criticism from viewers who accused Dr. Phil of exploiting her vulnerable state. Vivian Kubrick, daughter of The Shining director Stanley Kubrick, also criticized the show for lacking compassionate support.

Duvall passed away peacefully at her residence in Blanco, Texas, as confirmed by her partner, Dan Gilroy.

Duvall was awarded the Best Actress prize at the Cannes Film Festival for her role in 3 Women and later received a Peabody Award for her acclaimed Faerie Tale Theatre series. Her career also earned her nominations for two Emmys, a BAFTA, and numerous other accolades.

The release date for The Forest Hills, which also features Edward Furlong and Dee Wallace, has not been announced yet.