10 Original Casting Choices That Would Have Ruined Famous Movies

7. Britney Spears - Allie Hamilton (The Notebook)

Britney Spears I'm not going to say anything about the quality of The Notebook itself, except for the fact that it's a movie renowned for its ability to make pretty much anybody cry, and that it's become a shorthand reference for "a rom-com that it's legitimately okay for men to like." The film, of course, stars Ryan Gosling, who was - rather bizarrely - hired at the time because he "wasn't attractive," which I'm pretty sure nobody will agree with now. The Notebook also starred Rachel McAdams in what considered to be her breakthrough role. Whether or not you like The Notebook, or think that it's just another Nicholas Sparks pile of crap, you can't deny that it's a famous movie, and one that would have been made significantly worse had the producers gone with their original plan to cast Britney Spears, who - it's rumoured, anyway - was the frontrunner 'til McAdams blew everyone away in auditions. Phew.

All-round pop culture obsessive.