By Wendy Mitchell
Updated September 01, 2009 at 12:00 PM EDT

Lena Headey, star of 300 and Terminator: The Sarah Connor Chronicles, will join HBO’s fantasy pilot Game of Thrones. The Hollywood Reporter confirms that she will play Queen Cersei in the adaptation of the George R.R. Martin fantasy book series. The cast also includes Sean Bean, Mark Addy, Nikolaj Coster-Waldau and Peter Dinklage.