Hollywood star Jake Gyllenhaal says the cult sci-fi film, Donnie Darko, not only changed his career, but life too.

As the film completed 20 years since release, the actor looked back at memories associated with the film in an Instagram post.

"Pulled out my script and some artifacts from ‘Donnie Darko'... It was released 20 years ago. It's a film that changed my life and my career and it's been unreal to watch this story find afterlives with new audiences and new generations, and yet, what Donnie said to Roberta Sparrow is still true: "there is so much to look forward to"," he wrote on Wednesday.

"Thank you to all the fans who've come up to me over the years with that confused look on their faces and asked me: ‘what the f**k is Donnie Darko about??' Happy 20th Donnie! Let's keep confusing people. Here's to 20 more," he added.

The post came with photographs of personal notes, polaroids from the film, and a script of a scene.

Donnie Darko featured Gyllenhaal in the title role, along with his sister Maggie Gyllenhaal. the film also featured Mary McDonnell, Patrick Swayze, Drew Barrymore, Jena Malone, Holmes Osborne, Noah Wyle, Beth Grant and Katharine Ross in special roles.

Directed by Richard Kelly, the 2001 release, set in 1988, narrated the story of a troubled teenager who is visited at night by his imaginary friend named Frank, a haunting figure wearing a large rabbit suit. It follows the title character as he goes on a journey to find the true meaning behind his doomsday visions.