Gary Oldman
Winston Churchill
Acting
Stephen Dillane
Viscount Halifax
Acting
Lily James
Elizabeth Layton
Acting
Ronald Pickup
Neville Chamberlain
Acting
Ben Mendelsohn
King George VI
Acting
Kristin Scott Thomas
Clemmie
Acting
Nicholas Jones
Sir John Simon
Acting
Samuel West
Sir Anthony Eden
Acting
David Schofield
Clement Atlee
Acting
Richard Lumsden
General Ismay
Acting
Malcolm Storry
General Ironside
Acting
Hilton McRae
Arthur Greenwood
Acting
Benjamin Whitrow
Sir Samuel Hoare
Acting
Joe Armstrong
John Evans
Acting
Adrian Rawlins
Air Chief Marshal Dowding
Acting
David Bamber
Admiral Ramsay
Acting
Paul Leonard
Admiral Dudley Pound
Acting
David Strathairn
President Roosevelt (voice)
Acting
Eric MacLennan
Tom Leonard
Acting
Philip Martin Brown
Sawyers
Acting
Demetri Goritsas
Cabinet Secretary Bridges
Acting
Jordan Waller
Randolph Churchill
Acting
Alex Clatworthy
Diana Churchill
Acting
Mary Antony
Mary Churchill
Acting
Bethany Muir
Sarah Churchill
Acting
Anna Burnett
Pamela Churchill
Acting
Jeremy Child
Lord Stanhope
Acting
Brian Pettifer
Lord Kingsley Wood
Acting
Michael Gould
Lord Londonderry
Acting
Paul Ridley
House of Commons Speaker
Acting
Robin Pearce
Ernle Hastings
Acting
Michael Bott
Equerry
Acting
Olivier Broche
Reynaud
Acting
Mario Hacquard
Daladier
Acting
Pip Torrens
BBC Producer
Acting
Edmund Wiseman
Actor
Acting
Hannah Steele
Abigail Walker
Acting
Nia Gwynne
Alice Simpson
Acting
Ade Dee Haastrup
Marcus Peters
Acting
James Eeles
Maurice Baker
Acting
Flora Nicholson
Jessie Sutton
Acting
Bronte Carmichael
Young Girl on Tube
Acting
Roisin O'Neill
Agnes Dillon
Acting
John Locke
Oliver Wilson
Acting
Joanna Neary
Margaret Jerome
Acting
Richard Glover
Brigadier Nicholson
Acting
Tom Ashley
Ramsay Staffer
Acting
Joshua Higgott
Reporter
Acting
Imogen King
Teenage Girl at Tube Map
Acting
Miles Gallant
Naval Map-Room Officer
Acting
Faye Marsay
Sybil
Acting
John Atterbury
Sir Alexander Cadogan
Acting
James Harkness
AD Nicholl (Secretary #1)
Acting
Joshua James
W D Wilkinson (Secretary #2)
Acting
Charley Palmer Rothwell
Christopher Wilson (Photographer)
Acting
Patsy Ferran
Maid
Acting
Sarah Flind
Cook
Acting
Steffan Donnelly
Back Bencher
Acting
Kieran Buckeridge
Cecil Beaton
Acting
Johnny Otto
Member of Parliament (uncredited)
Acting
Nick Howden-Steenstra
Sentry (uncredited)
Acting