The role of RP McMurphy in 'One Flew Over the Cuckoo's Nest' required an actor of high caliber. Somehow, they had to make the career criminal lovable and relatable, and bring color to an extremely difficult topic. Only the best of the best were considered, and the charismatic Jack Nicholson took home a 'Best Actor' Oscar for his terrific performance. Gene Hackman was in the audience that night, applauding and regretting his life choices.
Hackman had been offered Nicholson's part, feeling burnt-out from filming 'The French Connection' and wanting to take a longer break before stepping back in front of the cameras. If he wanted someone to share his regrets with, he could have found the legendary Marlon Brando for a chat - Brando passed on the role as well! Hackman's career turned out just fine in the long run, but McMurphy is the kind of part that any actor should want.