The Worst Casting I Ever Saw

Jean Peters as Catana, a Spanish peasant girl in Captain From Castile. And her love interest, Tyrone Power (in the title role) wasn't much better. Dancing together, they generated about as much heat as a couple of the marionettes from Pinocchio (only the marionettes weren't nearly as wooden).

The main problem with Tyrone Power, imo (apart from his being about twice the age of his character, Pedro de Vargas), is that he was of Irish descent, but looked like most people's idea of a Spaniard. In the original novel, Pedro had red hair and green eyes--in other words, he was a Spaniard who looked like most people's idea of an Irishman!