'Game of Thrones' Casts Prominent Season 4 Role

"Graceland" actor Pedro Pascal will appear on the HBO drama as Prince Oberyn Martell, "The Red Viper."
Pedro Pascal

Game of Thrones has made its first big cast addition to the fourth season.

A HBO rep confirms that the drama has tapped Chilean actor Pedro Pascal to play Prince Oberyn Martell, as first reported by EW. Also referred to in the George R.R. Martin books as "The Red Viper," Martell arrives in King's Landing during the fourth season from the Dorne -- a previously unseen peninsula in the seven kingdoms of Westeros.

PHOTOS: 'Game of Thrones'' Most Gruesome Deaths: From Robert Baratheon to the Red Wedding

Martell's sister Elia was murdered by Gregor Clegane (Ian Whyte) during the Robert Baratheon and the Lannisters' overthrowing of Mad King Aerys. Clegane, still alive, has not seen since the second season.

Pascal has been adding multiple credits to his TV résumé of late. In addition to arcs on Graceland and Red Widow, he also has appeared on Nikita, Body of Proof and The Good Wife.

Pascal is repped by Innovative Artists and Authentic Talent and Literary Management.