I know that we all lampoon the casting of George Hamilton as Michael's lawyer in GFIII and Eli Wallach as Don Altobello. However, I watched (again) part of The Conqueror starring John Wayne as Ghengis Khan. Madonne! John Wayne at the height of his popularity being cast like that. That's the all-time example of just downright goofy casting.

"Generosity. That was my first mistake."
"Experience must be our only guide; reason may mislead us."
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