In 2009, Todd Phillips would lead the way, directing 'The Hangover'. At the start, there wasn't much to expect from the film, with a budget of $35 million. The film became a sensation, bringing in $469 million worldwide at the box office and it would lead to a trilogy of films.

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Casting the film wasn't easy and in fact, getting some of the film's biggest stars took quite the effort. Zach Galifianakis wasn't easy to track down and he initally turned down the role, according to the 'Hollywood Reporter', "When we were writing, we did have [other actors] in mind. Quite honestly, we were writing the brother-in-law as a younger brother they had to take along with them — like a Jonah Hill character instead of Zach [Jake Gyllenhaal also was considered]. Then we thought it’d be so much more awkward if it was an older brother who’s still at home. [Thomas Haden Church was strongly considered.] I’ve always been a huge fan of Zach [as a comedian and actor], but Zach didn’t want to come out and meet with me."

Wisely, Zach took the role and it changed his career. However, some would probably learn to regret the decision of turning the film down. One of those people was Lindsay Lohan, who just prior to film, was struggling with her image behind the scenes. Had she taken the role, it could've changed everything for her career. We'll discuss what part she was up for and why she decided to turn it down. But before that, let's take a look at her career during that time period.

Career Downfall

The film was released in 2009 and in 2007, just two years prior, things started turning south for Lindsay Lohan. At that point, she already had two driving under the influence felonies, along with several rehab stints. From that point on, the media took a big interest in her spiral, as she admitted with CNN, "And from then on, the press were on me all the time,” Lohan said. “It was the first time I’d taken drugs. I was out in a club with people I shouldn’t have been with, and took cocaine, and got in the car. It was so stupid.”

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Ultimately, her rehab stint helped a great deal, "I look at it as a good thing,” she said about this rehab visit. “I can come back afterwards and be fully focused on work. But I think there are other things I could do instead of going to a rehab center that would benefit me more. The best thing they could do for me would be to make me go abroad to different countries and work with children.”

When casting for 'The Hangover', Phillips wanted Lohan for the part of the stripper, which turned out to be a pretty great role and one that could've changed Lohan's career trajectory.

Lohan Said No

the hangover heather graham
via YouTube

Lohan met with Phillips and it is said that she loved the script. However, the biggest problem was the age factor. According to Phillips, this caused her to turn the project down, "I did meet with Lindsay Lohan a little bit [before casting Heather Graham], and we talked. Honestly, it felt like she ended up being too young for what we were talking about. People love to attack her for everything, like: “Ha, she didn’t see how great The Hangover was going to be. She turned it down.” She didn’t turn it down. She loved the script, actually. It really was an age thing."

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Heather Graham would get cast in the film and she played the role perfectly. It also would help that she was almost double the age of Lohan at the time at 37, "I found the character to be complex. Even though she’s a stripper, I loved that she’s also this genuine, emotional person. She met Stu and fell in love with him."

Others weren't as picky with the context of their characters. Alongside Daily Mail, Tyson admitted that he didn't understand what he got himself into till he began shooting for the film. The role worked out perfectly for Tyson as it did wonders for his image, "They said, "We're going to be shooting a movie with you in two weeks." I didn't even know. I said, "Really?!," and I started drinking with them. I was a little wasted at the time,' Tyson reveals. 'I still didn't understand the movie until like a week and a half later, when I was on set with these guys."

Things could've been much different had Lohan appeared in the film. Who knows how it might've shaped her career in a different direction.

NEXT - 'Mean Girls': Here's Why Lindsay Lohan Turned Down The Role Of Regina George

Sources: Daily Mail, CNN, The Hollywood Reporter & YouTube