Los Angeles, March 4 -- The cast of "A Knight of the Seven Kingdoms" has been expanded for its upcoming second season, bringing Lucy Boynton, Babou Ceesay and Peter Mullan into the growing "Game of Thrones" universe.

Boynton will portray Lady Rohanne, while Ceesay takes on the role of Ser Bennis. Mullan has been cast as Ser Eustace Osgrey. The drama is set roughly 90 years before the events of "Game of Thrones", during a time when the Targaryen dynasty continues to rule from the Iron Throne.

Boynton is known for roles in "A Cruel Love: The Ruth Ellis Story" and "Bohemian Rhapsody", reports DEADLINE.

The well-received first season ended on HBO on February 22, starring Pete Claffey as awkward hedge knight Ser Duncan 'Dunk' the Tall and Dex...