What if some of your favorite movies were played by different actors? Everything would be different! And it almost happened! Here are some 30 movies that almost starred some other famous person. Check it out below:

1. Christina Aguilera was offered the role of Alison Scott in "Knocked Up." The role went to Katherine Heigl instead.

2. Liam Neeson turned down a role to play President Abraham Lincoln in "Lincoln", which went to Daniel Day-Lewis.

3. Katie Holmes could have starred in "Cruel Intentions." It went to Reese Witherspoon. Better choice!

4. "Heathers" was originally written for Jennifer Connelly, but went to Winona Ryder.

5. Ashton Kutcher tried out for "10 Things I Hate About You" but was beat by Heath Ledger.

6. Jennifer Lawrence could have been a vampire. She lost the part of Bella in the Twilight series to Kristen Stewart.

7. Britney Spears was rumored for the role of Allie in "The Notebook". Thank goodness she didn't get it. Rachel McAdams was perfect!

8. Leonardo DiCaprio was supposed to star as Max Dennison in "Hocus Pocus", but turned down the role to star in "What's Eating Gilbert Grape."

9. Jennifer Hudson was considered for the lead role in "Precious" but turned it down. It was finally given to Gabourey Sidibe.

10. Catwoman in "Batman Returns" was almost played by Annette Bening, which thankfully didn't happen, because Michelle Pfeiffer was so much better!

11. Mindy Kaling wanted to be one of the "Bridesmaids", but lost it to Maya Rudolph instead.

12. Julia Roberts could have been in Sleepless in Seattle. Thankfully Meg Ryan landed the role instead.

13. Sam Worthington shot to fame with "Avatar" because Matt Damon turned it down to star in "Green Zone" instead.

14. Al Pacino was offered the role of Han Solo in "Star Wars". That would have been really, really, weird.

15. Cameron Crowe wrote "Jerry Maguire" with Tom Hanks in mind, but Tom Cruise was a better choice. More intense! Hanks was busy directing "That Thing You Do."

16. Tom Cruise was supposed to be Ren McCormack for "Footloose." But since he was busy, Kevin Bacon got the role instead.

17. John Travolta probably wouldn't have been a great Forest Gump. Tom Hanks landed the role, and he even won an Academy Award for it.

18. Johnny Depp was supposed to play Patrick Bateman in "American Psycho." Then after him, Leonardo DiCaprio, Brad Pitt and Ewan McGregor turned it down. This was Christian Bale's iconic role.

19. Brad Pitt was almost Russell Hammond in "Almost Famous" but dropped out to make way for Billy Crudup to take over.

20. Leonardo Dicaprio passed on playing Dirk Diggler in Boogie Nights, which went to his friend Mark Wahlberg after that.

21. Reese Witherspoon was almost Cher in "Clueless". Alicia Silverstone was a much better choice.

22. Cameron Diaz was supposed to be the lead in "The Princess Diaries" before they decided on Anne Hathaway instead.

23. Matthew McConaughey and Macaulay Culkin were considered for Jack's role in Titanic. Leonardo DiCaprio got it.

24. Lindsay Lohan’s role in "Confessions of a Teenage Drama Queen" was first offered to Hilary Duff.

25. Jessica Simpson would have made a lousy Jamie Sullivan in "A Walk To Remember." Mandy Moore is so much better!

26. Kelly Osbourne was supposed to get a role in "Freaky Friday." Lindsay Lohan got it instead. 

27. Vivian Ward in "Pretty Woman" was almost played by Molly Ringwald. This is so Julia Roberts' role.

28. Can you imagine Indiana Jones played by Tom Selleck? Nope, that would have been wrong!

29. Brad Pitt almost lost the part of Tyler Durden in Fight Club to Sean Penn.

30. Will Smith was supposed to be Neo. Of course, you can't ever imagine the Matrix being played by someone else other than Keanu Reeves.