In “Game of Thrones,” the veteran actor, David Bradley played the role of Lord Walder Frey a bitter old coot best remembered for one horrible event: the Red Wedding. Bradley is also well-known for playing Argus Filch, an old man who skulked around the castle with his cat, Mrs. Norris, in “Harry Potter.”
"Game of Thrones" fans obviously remember Michelle Fairley as Catelyn Stark, wife of Ned Stark and mother to Robb, Sansa, Arya, Bran, Rickon, and the "illegitimate" Jon Snow. Fairley also appeared in the "Harry Potter" franchise as Hermione's mom in "Harry Potter and the Deathly Hallows Part 1.”
Julian Glover plays the role of the cunning, deceptive, and outright loathsome Grand Maester Pycelle who kicks off the show's central conflict between the Lannisters and Starks in “Game of Thrones.” Surprisingly Glover is also the voice behind Hagrid's monstrous pet spider, Aragog in "Harry Potter and the Chamber of Secrets."
As Mance Rayder, self-anointed King Beyond the Wall in "Game of Thrones," Ciarán Hinds commanded practically every scene he was in until his untimely demise on the show. Hinds also appeared in "Harry Potter and the Deathly Hallows: Part II" and played the role of Dumbledore's bitter brother Aberforth.