Game of Thrones is an American medieval fantasy television series created for HBO by David Benioff and D. B. Weiss, featuring a predominantly British and Irish cast. The series is based on author George R. R. Martin's best-selling A Song of Ice and Fire series of seven planned fantasy novels, the first of which is A Game of Thrones. The series debuted in the U.S. on Sunday evening, April 17, 2011.