Donnie Darko could have been a very different movie. Any film or television buff knows that casting is basically half the battle when trying to make a great piece of art. After all, could you imagine a show like Seinfeld without its amazing cast? Heck, even the success of Wishbone relied on hiring the right dog. Well, Donnie Darko really needed a strong cast. Richard Kelly's original script wasn't something that everyone in the studio system could get on-board with right away. It was just too unique and 'heady' for some. But an approachable cast helped sell it to movie-goers... Or... at least DVD-buyers as Donnie Darko is a certifiable cult-classic that didn't find its audience until after its DVD release. Part of that had to do with the success that Jake Gyllenhaal found.

There are many things we don't know about Jake Gyllenhaal and this includes that he actually wasn't supposed to play the titular character in Donnie Darko. As we've learned from a fantastic article by The Ringer, that job was originally Jason Schwartzman's. Here's why Jake replaced him...

The Script Found Its Way Into Jason's Hands

After Richard Kelly wrote Donnie Darko he was smart enough to get his script into the hands of various agents at CAA and producers all over Hollywood. Because of that, a number of established stars started to read the unique screenplay. Despite the fact that the likes of Sydney Pollack, Joel Schumacher, and Betty Thomas were all reading the script, Richard maintained his position on wanting to direct it himself.

"The script went out to everyone. Every big producer in town wanted to meet me. I did the whole tour," writer/director Richard Kelly said to The Ringer. "Then Jason Schwartzman read the script because the script kept floating around."

According to Donnie Darko's producer Sean McKittrick, Jason was 'really into the script' and got a meeting with them.

"God bless Jason Schwartzman. That meeting, he became attached," Richard said. "This is in late ’99 or the very beginning of 2000. When Jason became attached, all of a sudden it legitimized me as a director."

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Because of this, Drew Barrymore's producing partner (Nancy Juvoen) wanted to read the script and introduced Richard to Drew. She was immediately cast in the movie.

"You have so much trust in someone when they write something so extraordinary as his script," Drew Barrymore said. "And then speaking with him, the fact that he was able to articulate all the genius that resides inside of him, I was so excited."

With Jason and Drew/Drew's production company attached, Richard Kelly was able to solidify his role as director and secure $4.5 million for the budget. However, Drew's involvement ended up causing Jason to leave the movie.

When Drew Accidentally Forced Jason Out Of Donnie Darko

The future of Donnie Darko was predicated on Drew Barrymore's involvement, but this ended up being the end of Jason Schwartzman's involvement with the flick.

"We had Drew for one week and she was our key to the financing," Richard explained. "We had to go into production later in the summer of 2000 or we were going to lose Drew."

Drew Barrymore was very busy... and so was Jason... Because of the schedule shifting, Jason was forced to leave Donnie Darko to fulfill a contract to another movie.

"Jason fell out of the movie, and we’re like, 'Holy s***! We’ve got to hit this date.'" Sean explained.

Enter Jake

Jason leaving Donnie Darko left Richard Kelly and Sean McKittrick with a massive problem on their hands... Who would play Donnie? But this problem opened up the door to a new opportunity.

"When we lost Jason, we met with every young actor in town," Richard explained. "It was really exciting. I remember Patrick Fugit from Almost Famous, we had a great meeting with him. Lucas Black from Sling Blade."

And then Jake Gyllenhaal walked in the door...

"The moment Jake walked in, it was like Holden Caulfield walked in. Richard gave me this look like, 'Oh, this is fucking him,'" Sean said.

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"I remember pulling over to the side of the road to finish reading Richard’s script and being mesmerized," Jake Gyllenhaal told The Guardian in 2016. "It was clearly influenced by classic directors—Ron Howard, Steven Spielberg—but with this strange psychosis. It beautifully captured the experience of moving into adulthood: the world that felt so solid becoming movable and liquid. I thought, 'This is what my adolescence felt like,'  although I don’t speak, and have never spoken to, rabbits."

Because of Jake's work in October Sky, Richard knew that Jake could take an entire feature film on his shoulders. But it was Jake's connection to the role, both emotionally and physically, that caught Richard's eye.

"He was kind of going through an emo stage," Richard explained. "I remember he showed up to the meeting and he had a metal chain belt, his hair was kind of spiked up. He was 19 playing 16, so it wasn’t too far off."

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