Game of thrones A Storm of Swords

Game of Thrones Season 3: Ramsay Bolton Cast?

Game of Thrones might have just cast one of the most notable new characters of its third season. Recent casting reports have shown that actor Iwan Rheon has been cast in an unspecified role in the season, though rumors are abounding that he's been cast in the pivotal role of Ramsay Bolton.
Rheon was not amongst the many new cast members revealed at Comic-Con, meaning that he has been cast relatively recently. His casting agency recently updated his CV to list the character "Boy" in Game of Thrones, listed as working under "various" directors (implying multiple episodes). Seeing as part of Bolton's storyline involves hiding his true identity, listing the character as "Boy," makes sense -- and it also helps to conceal any possible spoilers.
In A Song of Ice and Fire, the book series upon which Game of Thrones is based, Ramsay Bolton is the sadistic son of one of Robb Stark's top men, Roose Bolton (the guy who argued with Robb about torturing prisoners of war). While his father is cruel, Ramsay is purely unhinged, and is quite arguably one of the few truly evil characters in the series. His interactions with Theon Greyjoy will undoubtdly be some of the most disturbing parts of the series as well.
Rheon, who has long been a fan favorite casting choice for the role, is most famous for his starring role in the first three series of the Channel 4 drama Misfits, in which he played Simon Bellamy. Rheon has also made appearances on the television shows Grandma's House and Secret Diary of a Call Girl.
Game of Thrones season 3 will premiere on March 31, 2013.

^{Source:http://www.tvrage.com/news/1283/game-of-thrones-season-3-ramsay-bolton-cast}