Saoirse Ronan and Margot Robbie, probably two of Hollywood’s hottest actresses at the moment, put together a stirring performance as British royalty in “Mary Queen of Scots,”, back when it meant something to be king or queen of England. The film also stars Jack Lowden, Joe Alwyn, Gemma Chan, Martin Compston, Ismael Cordova, Brendan Coyle, Ian Hart, Adrian Lester, James McArdle, David Tennant and Guy Pearce.