Red Mercury starred the English actor who also played whom in the Harry Potter series?
Red Mercury (film): Red Mercury is a 2005 British film thriller directed by Roy Battersby and starring Stockard Channing, Pete Postlethwaite, Juliet Stevenson, Ron Silver and David Bradley. David Bradley (actor): David John Bradley (born 17 April 1942) is an English actor. David Bradley (actor):  He is best known for playing Argus Filch in the ""Harry Potter"" film series, Walder Frey in the HBO series "Game of Thrones" and Abraham Setrakian in "The Strain", although he is also an established stage actor with a career that includes a Laurence Olivier Award for his role in a production of "King Lear".
Argus Filch