With actors and actresses using their own quirks to make a role their own, it can often seem like a character was built for the performer, rather than the other way around.
That's why we need to talk about the 10 iconic characters that could have looked very different.
Whether it was a reluctant performer or stubborn producers, these stars almost missed out on some of their most recognisable film and TV roles.
Side note: Even Celebrities Need Wingmen. Post continues below.
From Wolverine to Harry Potter, here are the roles that could've looked very different.
Daniel Radcliffe on Harry Potter.
Yep, the boy who lived might have been played by another actor if Daniel Radcliffe's parents had put their collective feet down.
"The deal was to sign on for - I think - six films, all to be done in LA, and my mum and dad simply said, 'That's too much disruption to his life. That's not gonna happen,'" Radcliffe told the Hollywood Reporter in 2011.
"The deal had changed, and it was gonna be to shoot two films, and they'd both be done in England, and so they said, 'Okay, we'll let him audition'," the actor said. "And then it all went from there, really."
Can you imagine if Radcliffe wasn't Harry Potter? (Well, let's be honest, they will probably do a reboot very soon and another young actor will take his place.)
Lea Michele on Glee.
Lea Michele was in an accident that almost prevented her from auditioning for Rachel Berry on Glee.
But, in typical Rachel Berry fashion, even a car crash couldn't stop her from reaching for her dreams.
Side note: Listen to Cancelled where hosts Clare and Jessie cancel Lea Michele. Post continues below.