Helen Mirren as The Queen

Michael Elwyn as Anthony Eden

Haydn Gwynne as Margaret Thatcher

Richard McCabe as Harold Wilson

Nathaniel Parker as Gordon Brown

Paul Ritter as John Major

Rufus Wright as David Cameron

Edward Fox as Winston Churchill

David Peart as James Callaghan / Private Secretary

Geoffrey Beevers as Equerry

Nell Williams as Young Elizabeth

Charlotte Moore as Bobo MacDonald / Private Secretary

Harry Feltham as Junior Equerry / Footman

Matt Plumb as Junior Equerry / Footman

Spencer Kitchen as The Queen's Dresser

Elaine Solomon as The Queen's Dresser

Jonathan Coote as Cecil Beaton / Detective

Ian Houghton as Detective / Policeman