1. Britney Spears as Allie Hamilton in The Notebook. Via newsgab.com According to reports, Britney was very close to getting the role — without a doubt, producers were looking to tap into her fan base. But can you really imagine this role with anyone other than Rachel McAdams? Think about it... Or maybe it's best if you don’t. 2. Sarah Michelle Gellar as Cher Horowitz in Clueless. Via images.fanpop.com Sarah was originally supposed to play Cher but had to turn down the role due to a scheduling conflict with her TV work on All My Children. 3. Molly Ringwald as Vivian Ward in Pretty Woman. Yup, Molly reportedly turned down the role that catapulted Julia Roberts to superstardom. 4. Gwyneth Paltrow as Rose DeWitt Bukate in Titanic. Gwyneth was James Cameron’s first choice to play Rose — she turned it down. She reportedly told the press that the movie wasn't her "cup of tea." So now the real question: Would we hate Gwyneth as much as we do if she had been cast in one of the most beloved films of all time? That’s a trick question: Of course we would! 5. Bette Midler as Deloris Van Cartier/Sister Mary Clarence in Sister Act. Bette was originally in talks to play the role but backed out because she reportedly didn't want to portray a nun. 6. Marilyn Monroe as Holly Golightly in Breakfast at Tiffany's. Via cerdomus.com In one of the most iconic scenes in film history, it would be impossible to think of anybody other than Audrey Hepburn wearing the "Little Black Dress" while looking into the window of Tiffany’s. Well, if it had been up to the author of the books on which the movie is based, Truman Capote, it would have been Marilyn. In fact, he wrote the book with her as the character in mind. Even the movie's screenwriter, George Axelrod, wrote the script tailored to her. Marilyn was actually talked out of taking the role by her acting coach, Lee Strasberg — he felt that playing a prostitute would be bad for her image. When Audrey was cast, Capote remarked: "Paramount double-crossed me in every way and cast Audrey.” 7. Diana Ross as Rachel Marron in The Bodyguard. Via rankopedia.com Lawrence Kasdan’s script for The Bodyguard was first pitched around in 1975. The studio involved wanted Diana for the lead role and Steve McQueen in the Kevin Costner role. (I, for one, would really like to have seen this version.) Unfortunately, the movie fell apart in the development stage — and another 57 times — before it was finally made in 1992. 8. Madonna as Ginger McKenna in Casino. Via madonnascrapbook.blogspot.com Sharon Stone got a Best Actress Oscar nomination for her performance in Casino, but it never would have happened if Martin Scorsese had gone with his original choice for the role, Madonna. 9. Natalie Portman as Juliet Capulet in Romeo + Juliet. Via wallpaperfetch.com Natalie had been cast in the role, but after production began, Baz Luhrmann felt that due to her and Leonardo DiCaprio's age difference, the footage shot made it look as though Leo was "molesting" her. 10. Halle Berry as Annie Porter in Speed. Halle turned down the role that made Sandra Bullock a star. 11. Drew Barrymore as Nomi Malone in Showgirls. Drew reportedly passed on the role due to the amount of nudity that would be required. Also, producers wanted Madonna in the role of Cristal Conners — which might have taken the movie to a new level of camp. 12. Charlize Theron as Roxie Hart in Chicago. Charlize had the role of Roxie Hart, while Nicholas Hytner was attached as director. When Hytner left the project and Rob Marshall took over, Charlize had to audition again and ended up losing the role to Renée Zellweger. 13. Emma Thompson as Catherine Tramell in Basic Instinct. Via elespectador.com Emma was considered for the role but reportedly passed on the chance so she could work on Howards End. Emma commented years later, "I could never have pulled it off — excuse the expression — as good as Sharon." 14. Michelle Pfeiffer as Clarice Starling in The Silence of the Lambs. Jodi Foster's Oscar-winning role could have gone to Michelle Pfeiffer, who was offered the role first, but she reportedly turned it down due to the violent story line. 15. Reese Witherspoon as Sidney Prescott in Scream. After Drew Barrymore was forced to give up the role of Sidney, due to scheduling conflicts, the producers offered the role to Reese. She passed. 16. Julia Roberts as Viola De Lesseps in Shakespeare in Love. Via fashiondicas.net Julia Roberts was originally signed to star in the movie in 1993 but left the project after Daniel Day-Lewis declined to play the part of Shakespeare. 17. Bette Davis as Scarlett O'Hara in Gone with the Wind. Via doctormacro.com Gone with the Wind producer David O. Selznick wanted Bette for the role, but Warner Bros. (for whom Bette was signed under contract) would not allow her to accept unless Errol Flynn (another Warner actor) was cast as Rhett Butler. David refused to cast Errol, and Bette was forced to decline. Warner Bros. made the film Jezebel (about a Southern belle) as compensation for her losing the role. 18. Jennifer Connelly as Veronica Sawyer in Heathers. The role was written with her in mind, but she turned it down. It is blasphemy to even think that anyone other than Winona Ryder could have played that role! 19. Annette Bening as Catwoman in Batman Returns. Annette Bening was originally cast to play Catwoman but was replaced by Michelle Pfeiffer when she became pregnant a few weeks before filming began. 20. Shirley Temple as Dorothy Gale in The Wizard of Oz. Shirley was a huge star, and MGM tried to make arrangements to borrow her from 20th Century Fox (the studio that had her under contract), but negotiations fell through, and Judy Garland was cast — who, at the time, was relatively unknown.Also, it's best not to think how Shirley's version of "Over the Rainbow" would have sounded. Honorable mention: Lindsay Lohan as Jade in The Hangover. Via nonlypictures.blogspot.com Yup, Lindsay passed on the role of Jade in The Hangover after declaring the screenplay "had no potential." The role then went to Heather Graham.