9. Tyrion Lannister - Game Of Thrones
It would be reductive to suggest that Peter Dinklage was only perfect to play Game of Thrones' Tyrion Lannister because he too is a dwarf, but there's no denying that it's a defining aspect of the character and his success in securing the role.
Yet beyond being one of the most prominent dwarf actors working in Hollywood, Dinklage brought a necessary dimensionality to the table that helped quickly establish Tyrion as the show's breakout character.
Dinklage so perfectly captured the quick-witted Tyrion of George R.R. Martin's books, and perhaps by having to prove himself in an industry that offers so few legitimate opportunities to little people, he also tapped into the chip that Tyrion himself wears on his shoulder as the "runt" of the Lannister litter.
If many other actors truly could've played most of the show's principal parts, that's absolutely not the case with Tyrion, even taking his uncommon stature out of the equation.