When the young Earl of Leicester has risen against Elizabeth, she states "love does alter when it alteration finds". This is a reference to a line from Shakespeare's sonnet no. 116: "love is not love which alters when it alteration finds". Shakespeare lived during the reign of Elizabeth I, and owed his success in part to her support of the arts in general.
Barbara Flynn had portrayed Mary Queen of Scots onstage in 1995, co-headlining - with Janet McTeer as Queen Elizabeth - the Mermaid Theatre production of Robert Bolt's ''Vivat! Vivat Regina!''.
Both Helen Mirren and Barbara Flynn would portray Queen Elizabeth II onscreen, Mirren in both The Queen (2006) and The Audience (2013), Flynn in The Enemy Within (2009).