In 1970, before Coppola had taken the helm, author Mario Puzo scribbled and sent the following letter to Marlon Brando in an effort to cast him in the movie adaptation of his novel, The Godfather. The studio, well aware of Brando's recent bad form and notoriously overbearing demands, were less enthusiastic however, and refused to cast him despite his immediate interest. Had it not been for Coppola later coming on board and subsequently fighting for Brando's inclusion, Puzo's wishes could easily have been ignored.
(Source: Vanity Fair; Image of Brando via Decibel)
Dear Mr Brando,
I wrote a book called THE GODFATHER which has had some success and I think you're the only actor who can play the
partGodfather with that quiet force and irony the part requires. I'd love you to read the book and like it well enough to use whatever power you can to get the role. I'm writing Paramount to the same effect for whatever good that will do. I know this was presumptuous of me but the best I can do by the book is try. I really think you'd be tremendous. Needless to say I've been an admirer of your art.
A mutual friend, Jeff Brown, gave me your address